<span style="font-size:16px;"><span style="text-decoration:underline;"><b>Overclocking:</b></span></span><br>

Now that the new Vocabulary has been defined and you have all of the software and benchmarks installed and setup, it's time to move on to the main attraction <img alt="thumb.gif" class="bbcode_smiley" src="http://files.overclock.net/images/smilies/thumb.gif"><br>

There's two methods for overclocking: the long method that will result in a nearly perfect overclock; and the short method, where you'll get pretty close but it won't be the absolute max. Either method is fine, it just comes down to how much time you want to devote to your overclock. I will be explaining both methods below.<br><br><span style="text-decoration:underline;"><span style="font-size:16px;"><b>The Long Method -- Estimated Time: 3 Hours</b></span></span><br>

This method will get you to within about .25% of your card's maximum overclocked performance. Three hours is a lot of time, but you only need to do this one time and then your card is overclocked for the rest of it's lifespan. If you don't have the time or patience to devote three hours to this project, then skip down to the Quick Overclocking section of this guide.<br><br><b><span style="text-decoration:underline;">Finding your Maximum Stable Core Clock</span></b><br><br><b>Step one: Preparation:</b><br><ul class="bbcode_list"><li>Be sure your fan curve is setup like i mentioned above in the Precision-X setup section. It's important to keep your GPU under 70C at all times to prevent thermal throttling.</li>

<li>Temporarily increase both the Power Target and Voltage slider to their maximum value. This will minimize the throttling caused by going over the Power Target.</li>

<li>Go to the Nvidia Settings menu (you can open this from the taskbar), go to Manage 3d Settings, Global settings tab, scroll to the very bottom and make sure Vsync is set to off. You can turn this back on after you find your maximum overclock if you wish.</li>

<li>Increase the GPU Clock Offset by whatever it takes to get your Boost Clock to 1100MHz. So that means if you're using a reference model with a default Boost Clock of 980 you will need to increase the offset to +120. If you're using a Factory overclocked card, then you will need to increase the offset by +10 to +50 (or until you hit 1100MHz Boost Clock) depending on which card you have, just use GPU-Z to keep track of your Boost Clock. If you have an Asus TOP 670 then i suggest down-clocking the card by 37MHz (-37 offset) for now. The reason being, someone Asus TOP models are factory overclocked to an unstable level.</li>

</ul><br><br>

Now double-click on one of the graphs in Precision-X to bring up the expanded Hardware Monitor (you may need to click the 'Performance Log' button before you can do this). Right-click on the expanded hardware monitor and then click 'clear history'. Now start a run of Heaven Benchmark. This will give us some information about your card's overclocking capability. As soon as the Benchmark finishes, save your score (name it CC-MMM, where CC is your core offset, and MMM is your memory offset, so here it should be 120-000 or something similar), hit esc, and then quit Heaven. If you didn't make it to the end of the benchmark for whatever reason (ex, the benchmark crashed, your display drivers crashed and stopped responding, or you had a BSOD or a Red screen) or if you saw graphical artifacts during the benchmark (Bright green/blue spots), then skip to Step 4. If you made it through the benchmark, then right-click on the Expanded Hardware Monitor and click pause. It should look something like this:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/898764/width/568/height/446/flags/"><img alt="446" class="bbcode_img lightbox-enabled" data-id="898764" data-type="61" src="http://www.overclock.net/content/type/61/id/898764/width/568/height/446" style="width:568px;height:446px;"></a><br><ul class="bbcode_list"><li>Notice how the voltage is constant the entire time? That's because we increased the voltage to 1.175V in Precision-X which locks the voltage at the maximum during heavy load.</li>

<li>Now mouse through the Power Percent line and try to fine the highest peak. The lower this peak is, the better. A low power percent at this stage usually indicates you have a lot of overclocking headroom left</li>

<li>Now mouse through the GPU Clock. What you're looking for is a perfectly straight, constant line (some drops at the very beginning and end are normal). If the line isn't straight at this stage, then that's an indicator that your card is already being throttled and you have little to no more core overclocking headroom.</li>

<li>You can go ahead and calculate your Kepler Boost at this moment if you wish. Just take your Max Boost Frequency and subtract your Boost Clock. The higher your Kepler Boost, usually the better your card will overclock. Keep in mind though, this isn't a hard rule; some people with low Kepler Boosts can still get high overclocks.</li>

<li>Now mouse through the temperature line. You want to make sure that you didn't go over 70C. If you did, then refer to the troubleshooting section called "Reducing Temperatures to Eliminate Throttle" below. If your temperatures are below 70C, this is a good sign and means you can keep overclocking for now.</li>

</ul><br><br><b>Step 2: Increasing your offset:</b><br><br>

Increase the GPU Clock offset by an additional 20MHz, clear the Precision-X hardware monitor and unpause it, and start up a second Heaven Benchmark run. Immediately after the Heaven run completes, save your score (use a similar naming convention as you did above) and pause the Hardware Monitor. If you crashed or have any other symptoms of instability, go to Step 4. If your Heaven score decreased, that can mean one of three things. Either your overclock is unstable, your overclock is pushing you over the thermal or power throttle zone reducing your overall performance, or the benchmark was inconsistent. This is something that you need to be very vigilant of. Just because you hit a higher Max Boost frequency doesn't mean your GPU is performing better. Here's an example of what I'm talking about:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/898818/width/137/height/245/flags/"><img alt="245" class="bbcode_img lightbox-enabled" data-id="898818" data-type="61" src="http://www.overclock.net/content/type/61/id/898818/width/137/height/245" style="width:137px;height:245px;"></a><br>

Compare this graph to the one i posted above in Step 1. In the first graph my GPU core was at a constant 1241MHz the entire time. As you can see here, my Max Boosted Frequency has gone up to 1264 but there's a ton of oscillation and it's also dipping extremely low too, even down to my base boost clock of 1120. So even though my card momentarily has a higher Max Boost, my overall performance has decreased substantially. This is why it's extremely important to always analyze the graphs after each offset increase. Higher is not always better with Kepler GPUs. If this is what your GPU Clock graph looks like (and/or even if you're seeing small 13mhz drops), go on to Step 3.<br><br><span style="text-decoration:underline;">Here's an example of what a successful offset increase looks like:</span><br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/898829/width/148/height/241/flags/"><img alt="241" class="bbcode_img lightbox-enabled" data-id="898829" data-type="61" src="http://www.overclock.net/content/type/61/id/898829/width/148/height/241" style="width:148px;height:241px;"></a><br>

Now you see my Max Boost is running at a constant 1264 with no dips. This is what you want to see with each additional increase in offset. So as long as your Heaven score hasn't decreased, and your Max Boost is running at a constant Frequency, then this means you're ready to increase the offset some more. Keep repeating this step (step 2) until you meet the criteria to go on to another step.<br><br>

However, if your GPU clock doesn't show any variance, yet your Heaven score has decreased by more than 5 points, then i suggest that you re-run the Heaven Benchmark. If your score is still lower than the previous offset, then revert back to the previous Offset that had the highest score, and re-run Heaven again. If that score is still higher, then that suggests that your overclock with the increased offset is unstable. If this is the case, increase your offset back to the one that produced the <i>lower</i> score and then go to Step 4.<br><br><b>Step 3: Dealing with Frequency Oscillation:</b><br>

If you're on this step then that means you're seeing your Max Boost Frequency constantly changing which will often times result in a performance decrease. First, check that your temperatures are still under 70C at all times. If they are, then you know it's not your temperatures causing the problems. If your temperatures are going over 70C, then refer to the Troubleshooting section below, "Reducing Temperatures to Eliminate Throttle."<br><br>

Next, check to see if the Frequency drops also correspond with a GPU usage drop. If the GPU usage drops to less than around 90%, the GPU core clock might be throttled down just to save power but this won't lead to a performance decrease. Here's an example:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/899464/width/578/height/477/flags/"><img alt="477" class="bbcode_img lightbox-enabled" data-id="899464" data-type="61" src="http://www.overclock.net/content/type/61/id/899464/width/578/height/477" style="width:578px;height:477px;"></a><br>

You see how each time my GPU usage drops my core clock also drops? This is because whenever there's a drop in GPU demand, for example when you're on a loading screen between sections in a benchmark or game, the core clock also drops in order to save power. This is completely normal and just means the GPU is throttling itself whenever additional core frequency is <i>not</i> beneficial, so you aren't actually losing performance. If this is what you're seeing, then go back to Step 2 and ignore the frequency oscillation that also corresponds with GPU usages drops too.<br><br><br>

Now, check to see if your Power Percent is close to your set maximum Power Target (remember, Power Percent can go 3-10% over the set Power Target). So if your Power Target is set at 117%, and your Power Percent is at 120%-124%, then that is probably the reason for your oscillating frequencies. The only solution I've found to stabilize the variance in Max Boost caused by a maxed out Power Percent is to reduce the voltage slider. The reason this works is it reduces your Power Percent slightly but it might also cause instability. Try reducing the voltage slider back to default and check if your Max Boosted Frequency stabilize. Usually though, this method might stabilize your frequencies but it will cause instability too. If it causes instability, go to step 4. If not, and it fixed your oscillating frequencies, then go back to Step 2.<br><br><b>Step 4: Fixing Instability</b><br>

So either your application crashed or produced an error, your display driver crashed or became unresponsive, you Blue-screened, you've notice graphical anomalies or your Benchmark score has decreased, or changing voltage doesn't stabilize the variance in your Max Boost. This usually means you're over your maximum stable offset. The only way to make your card stable at this point is to reduce the offset. The first thing you'll need to do is save a profile of your current settings in Precision-X (this is done by clicking the profile button at the bottom-left and then right-clicking a number), now close Precision-X and re-open it. <span style="text-decoration:underline;">The reason you have to restart Precision-X after each crash is because Precision-X will sometimes get bugged and not transfer your settings to the GPU.</span> Restarting it is the only way to fix this. Now that you've restarted Precision-X, left-click on your saved profile and then click apply to load your previous settings, <span style="text-decoration:underline;">go to the voltage control and increase it to the max again (crashing resets voltage to default, and you can't save voltage in profiles)</span>. These underlined bits are extremely important. You will save yourself a lot of frustration later if just remember to restart Precision-X after each crash and then reset your voltage.<br><br>

Now reduce your core offset by 5Mhz, clear the hardware monitor (and unpause it if applicable), and start a Heaven run. After the heaven run completes, save your score and pause the hardware monitor. If you still crashed or had other symptoms of instability, keep repeating this step until you reach stability and you reach a flat-lined (ie, constant) GPU Clock on the Precision-X graph. Be sure you restart Precision-X and reset your voltage after each crash. If you reach stability with a constant GPU Clock, go to Step 5.<br><br><b>Step 5: Fine Tuning</b><br>

Now that you're within 4MHz of your maximum stable overclock, it's time to increase the offset in smaller steps. Increase the core offset by 1MHz, clear the hardware monitor (and unpause it if applicable), and start a Heaven run. After the heaven run completes, save your score and pause the hardware monitor. If this 1MHz increase caused instability again or the GPU clock to become variable (ie, not a constant line on the GPU clock graph), then reduce the offset by 1MHz and go to Step 6. If neither of these two scenarios happen, then repeat this step up four times and then go to Step 6.<br><br><b>Step 6: Checking for Instability in other Applications:</b><br>

Heaven Benchmark will get your GPU stable in about 99% of other games, benchmarks and applications, but it's still a good idea to test your overclock in a couple other applications just to be on the safe side. I'd suggest starting with 3dMark11, then any of the other free game benchmarks i posted above, then boot up a couple games that you typically play (BF3 multiplayer is usually a good stability testing game if you have it). If your GPU show signs of instability in any of these games or benchmarks, then reduce your core offset by 1MHz until the problem goes away.<br><br>

Now that you've tested your overclock in some other applications, it's safe to say that you've now found your maximum stable boosted frequency. I suggest that you save these settings in a Precision-X profile for future.<br><br><b><span style="text-decoration:underline;"><span style="font-size:12px;">Finding your Maximum Stable Memory Clock:</span></span></b><br><br><b>Step 1: Increasing your Memory Offset:</b><br><ul class="bbcode_list"><li>Revert your GPU Core offset to its default (+0) offset but leave the Power Target and voltage slider at whatever it took to stabilize your Core (most likely the maximum for both of these).</li>

<li>Increase your Memory Offset to +100</li>

<li>Start up a Heaven Benchmark run. <span style="text-decoration:underline;">Be extremely vigilant during the entire Benchmark run, you're looking for any graphical anomalies or artifacts</span>. These usually look like green, blue, or white light shafts or dots. I've found it's usually much easier to spot these if you move six feet away from your monitor so you can have most of the screen in visual focus. If you see any artifacts, go ahead and hit ESC and then click 'Quit' in the top-left menu to end the Benchmark early; there's no point in letting the Benchmark finish if you already know it's unstable. After the Heaven run completes, save your score (name it CC-MMM, where CC is your core offset, and MMM is your memory offset, so here it should be 00-100). If you crashed, saw any graphical artifacts or have any other symptoms of instability, or if your score decreased by more than 5 points, go to Step 2. If not, repeat this step until you do and then go to Step 2.</li>

</ul><br><br><b>Step 2: Fine Tuning your Memory Offset</b><br><ul class="bbcode_list"><li>Reduce your Memory Offset by 25Mhz. For example, if you were at +600 in Step 1 and that started to produce graphical anomalies, you should be at +575 now.</li>

<li>Start up a Heaven Benchmark run. Be sure you're still looking for graphical artifacts during the entire run. Once the benchmark finishes, save your score. If you crashed, saw any graphical artifacts or have any other symptoms of instability, or if your score decreased by more than 5 points, then repeat this step until the problem is resolved and then go to Step 3. Be sure that you restart Precision-X after each crash like i described in the Core Clock portion of this guide.</li>

</ul><br><br><b>Step 3: Fine Tuning your Memory Offset</b><br><ul class="bbcode_list"><li>Increase your memory Offset by an additional 5Mhz. For example, if you had to drop down to +525 Offset in Step 2 to eliminate artifacts, then you should be at +530 Offset now.</li>

<li>Start up a Heaven Benchmark run. Be sure you're still looking for graphical artifacts during the entire run. Once the benchmark finishes, save your score. If you crashed, saw any graphical artifacts or have any other symptoms of instability, or if your score decreased by more than 5 points, then repeat this step until the problem is resolved and then go to Step 4. Be sure that you restart Precision-X after each crash like i described in the Core Clock portion of this guide.</li>

</ul><br><br><b>Step 4: Fine Tuning your Memory Offset</b><br><ul class="bbcode_list"><li>Decrease your memory Offset by 1Mhz. For example, if you were able to increase your Offset to +540 in Step 3, then you should be at +539 now.</li>

<li>Start up a Heaven Benchmark run. Be sure you're still looking for graphical artifacts during the entire run. Once the benchmark finishes, save your score. If you crashed, saw any graphical artifacts or have any other symptoms of instability, or if your score decreased by more than 5 points, then repeat this step up to four times or until the problem is resolved and then go to Step 5. Be sure that you restart Precision-X after each crash like i described in the Core Clock portion of this guide.</li>

</ul><br><br><b>Step 5: Checking your Memory for Instability in other Applications</b><br><ul class="bbcode_list"><li>Like I mentioned in Step 6 of the Core overclocking section, it's a good idea to check for stability in other applications too. At the very least, check for stability on 3DMark11. If you see artifacts in any other application, reduce the Memory Offset by 1MHz until the problem goes away.</li>

<li>Now you know your maximum memory frequency. I suggest that you save this to a profile number.</li>

</ul><br><br><b><span style="text-decoration:underline;"><span style="font-size:12px;">Finding your Maximum Stable Total Overclock</span></span></b><br>

Now that you found your maximum core and memory overclock independently of each other, it's time to attempt to put them together. With some luck, you'll be able to put the two together and be stable right off the bat.<br><br><b>Step 1: Combing both Maximums</b><br>

Set Precision-X to your maximum core offset and maximum memory offset that you found in the above steps. Be sure the voltage is set to whatever you needed to stabilize your core clock (for most people, this should be maxed). Be sure the Power Target is also set to the max. Now clear the hardware monitor (and unpause it if applicable), and start a Heaven run. After the heaven run completes, save your score (name it CC-MMM, where CC is your core offset, and MMM is your memory offset) and pause the hardware monitor. If you crashed, saw artifacts, or had any other symptoms of instability, then go on to Step 2a. If not, then you're done! You're at your true maximum GPU overclock. Go on to the Fan section below.<br><br><b>Step 2a: Explanation of Core and Memory balance</b><br>

Most likely you crashed in Step 1 when you first combined both maximums. This is quite normal. From here you usually have three paths that you can take. Either you sacrifice some core frequency in-order to maintain your maximum memory frequency, you sacrifice some memory frequency to maintain your maximum core frequency, or you sacrifice a little of both. Neither option is better than another on the whole, it really depends on your specific GPU and how much you have to give up of one to maintain the other. Some GPU's barely have to give up any of one to maintain the other. Also, some applications benefit more from memory than core and vice versa. Generally speaking though, 1MHz on the core is worth about 4MHz on the memory in terms of performance, keep that ratio in mind as you reduce things.<br><br>

Based on a lot of trial and error with three difference GTX 670's (Asus TOP, Gigabyte Windforce, and an EVGA reference model) I've found that reducing both core and memory together produces the best results. When i only reduced the core frequency enough to stabilize the GPU I'd still have memory related artifacts. When i only reduced the memory, I'd have to give up a huge amount of memory to stabilize the GPU; I'd have to trade something in the ball park of 25MHz on the memory for 1MHz on the core, which if you remember the 1-4 ratio above, is a very poor trade. My maximum boosted frequency was also getting throttled by 13MHz at certain points in 3dMark11 because i was hitting the maximum Power Percent when i only reduced the memory. But when i reduced both together, I've found that i can keep both the core and memory frequencies rather high while eliminating the memory related artifacts without seeing a Power Percent throttle in 3dMark11. Because of this empirical evidence, I'm going to suggest in this guide that you reduce both together. It's up to you if you want to try the other two methods, they might net you slightly better performance.<br><br><b>Step 2b: Balancing the Core and Memory</b><br>

Close and then reopen Precision-X, re-enter your maximum offsets (or re-enter the Offsets you used in your previous run if you're repeating this step), Power Target, and voltage.<br>

Reduce the core offset by 1MHz and the Memory Offset by 5MHz. After the Heaven run completes, save your score. Keep repeating this step until you become stable enough to finish Heaven (ignore artifacts for now) and then go to Step 3.<br><br><b>Step 3: Finding your optimal Balance Point</b><br>

If you finished Heaven but still saw artifacts, then reduce the memory offset by an additional 5MHz until the artifacts go away. For every 5MHz you reduce the memory you can typically increase the core offset by an additional 1MHz. Be sure you don't increase the core offset higher than 1MHz below your maximum stable core offset. I've found that staying 1MHz below your maximum stable core offset allows you to increase the memory quite a bit more while still retaining stability without artifacts. Repeat this step until the artifacts are gone and you're still stable. If at some point you do become unstable again (if you crashed, remember to restart precision-X) reduce the core value by 1MHz but leave the memory where it was. If that is stable again, then continue the pattern until the artifacts are gone. Once the artifacts are gone and you can complete Heaven, go to the next step.<br><br><span style="text-decoration:underline;">Here's an example of Step 3</span>:

<a class="spoiler-link H-spoiler-toggle" href="#"><strong>Warning: Spoiler!</strong> <span class="spoiler-help">(Click to show)</span></a><div class="spoiler-hidden">Lets assume you became stable enough to complete Heaven at +119 core offset and +604 memory offset but you still have artifacts.<br>

So you reduce the memory by 5 and increase the core by 1 = +120c and +599m. You test this and you still have artifacts but you still can complete Heaven<br>

So you reduce the memory an additional 5 and increase the core by 1 = +121c and +594M. In this test you crash before you can complete Heaven (be sure to remember to restart Precision-X after the crash).<br>

Now instead of reducing the memory more, you reduce the core by 1 = +120c and +594M. You test this and you still have artifacts but now you can complete Heaven again.<br>

Now you reduce the memory by 5 and increase the core by 1 = +121c and +589M. You test this and you can finish Heaven and you no longer have artifacts.</div>

<br><b>Step 4: Fine Tuning the Memory Offset</b><br>

Leave the core offset where it is and increase the memory offset by 1. Repeat this step until you see artifacts or crash, in which case you'd reduce the memory offset by 1, or until you've repeated this step a total of four times.<br><br><b>Step 5: Checking for Instability in other Applications:</b><br>

Now, just like above, you should test your combined overclock in other applications. I'd suggest starting with 3dMark11, then any of the other free game benchmarks i posted above, then boot up a couple games that you typically play (BF3 multiplayer is usually a good stability testing game if you have it).<br><ul class="bbcode_list"><li>If you crash in any of these games or benchmarks, then reduce your core offset by 1MHz until the problem goes away. Just be sure the crash is not caused by the game itself before deciding to reduce things.</li>

<li>If you see graphical artifacts, reduce the memory offset by 1 until it goes away.</li>

</ul><br><br>

You should now be at your highest performing stable overclock. Go on to the Fan section of this guide.<br><hr class="bbcode_rule"><br><span style="font-size:16px;"><span style="text-decoration:underline;"><b>Quick Overclocking -- Estimated time: 30 minutes</b></span></span>

<a class="spoiler-link H-spoiler-toggle" href="#"><strong>Warning: Spoiler!</strong> <span class="spoiler-help">(Click to show)</span></a><div class="spoiler-hidden">Using this method should get you within about 2-5% of your card's maximum overclock but in a lot less time. For most people, overclocking using this method is probably ideal. If you followed the long overclocking section of this guide, skip this and go to the Fan section instead.<br><br><b>Step 1: Preparation:</b>

<ul class="bbcode_list"><li>Be sure your fan curve is setup like i mentioned above in the Precision-X setup section. It's important to keep your GPU under 70C at all times to prevent thermal throttling.</li>

<li>Temporarily increase both the Power Target and Voltage slider to their maximum value. This will minimize the throttling caused by going over the Power Target.</li>

<li>Go to the Nvidia Settings menu (you can open this from the taskbar), go to Manage 3d Settings, Global settings tab, scroll to the very bottom and make sure Vsync is set to off. You can turn this back on after you find your maximum overclock if you wish.</li>

<li>Increase the GPU Clock Offset by whatever it takes to get your Boost Clock to 1100MHz. So that means if you're using a reference model with a default Boost Clock of 980 you will need to increase the offset to +120. If you're using a Factory overclocked card, then you will need to increase the offset by +10 to +50 (or until you hit 1100MHz Boost Clock) depending on which card you have, just use GPU-Z to keep track of your Boost Clock.</li>

<li>Start a Heaven Benchmark run. If you make it to the end of the run, then go to Step 2, if you crash or have other signs on instability, go to Step 3</li>

</ul><br><b>Step 2: Finding your maximum core offset</b>

<ul class="bbcode_list"><li>Increase the core offset by an additional 20MHz</li>

<li>Start up another Heaven Benchmark run</li>

<li>If you make it to the end of this run, repeat this step until you crash or show signs of instability and then go to Step 3.</li>

</ul><br><br><b>Step 3: Finding your maximum core offset</b>

<ul class="bbcode_list"><li>Reduce the core offset by 5MHz</li>

<li>Start up another Heaven Benchmark run</li>

<li>If you <i>DON'T</i> make it to the end or show signs of instability, then repeat this step until you can finish Heaven and then go to Step 4.</li>

</ul><br><br><b>Step 4: Fine tuning your maximum core offset</b>

<ul class="bbcode_list"><li>Increase the core offset by 2MHz</li>

<li>Start up another Heaven Benchmark run</li>

<li>If you crash or show signs of instability, then remove that additional 2 core offset and go to Step 5.</li>

<li>If you don't crash or show signs of instability, then go to Step 5.</li>

</ul><br><br><b>Step 5: Finding your maximum memory offset</b>

<ul class="bbcode_list"><li>Now increase the memory offset by 100</li>

<li>Start up a Heaven Benchmark run</li>

<li>If you make it to the end <i>without</i> seeing any graphical artifacts and see your Heaven Score increase, then repeat this step until you crash, see artifacts, see your score decrease by more than 5 points, or show other signs of instability and then go to Step 6.</li>

</ul><br><br><b>Step 6: Finding your maximum memory offset</b>

<ul class="bbcode_list"><li>Reduce the memory offset by 25</li>

<li>Start up a Heaven Benchmark run</li>

<li>If you crash, see artifacts or show other signs of instability, then repeat this Step until you no longer do then go to Step 7.</li>

</ul><br><b><br>

Step 7: Finding your maximum memory offset</b>

<ul class="bbcode_list"><li>Increase your memory offset by 12</li>

<li>Start up a Heaven Benchmark run</li>

<li>If you crash, see artifacts, see your score drop by more than 5 points, or show other signs of instability, then remove the additional 12 memory offset you just added and go to Step 8</li>

<li>If you don't crash, see artifacts, see your score drop by more than 5 points, or show other signs of instability, then go to Step 8</li>

</ul><br><br><br><b>Step 8: Checking for Instability in other Applications:</b><br>

Heaven Benchmark will get your GPU stable in about 99% of other games, benchmarks and applications, but it's still a good idea to test your overclock in a couple other applications just to be on the safe side. I'd suggest starting with 3dMark11, then any of the other free game benchmarks i posted above, then boot up a couple games that you typically play (BF3 multiplayer is usually a good stability testing game if you have it).<br><ul class="bbcode_list"><li>If you crash in any of these tests, then reduce your core offset by 2 until you stop crashing</li>

<li>If you see artifacts, then reduce your memory offset by 5 until you stop seeing artifacts</li>

</ul><br><br>

Congratulations, you're now very close to your maximum overclock. Go on to the Fan section of this guide.</div>

<hr class="bbcode_rule"><br><b><span style="text-decoration:underline;"><span style="font-size:16px;">Setting up a Quiet and/or Efficient Fan Curve:</span></span></b><br>

There's a couple of ways to go about this. Either you setup a fan curve that maximizes performance or you setup a fan curve that's quiet but sacrifices a small amount of performance. If you have a 670 with non-reference cooling (specifically the Gigabyte Windforce, both Asus models, or the factory overclocked Galaxy model) you can easily get away with a very quiet fan profile without sacrificing performance. However, with the turbine-cooled reference models, you'll most likely have to choose between a quiet profile or maximum performance. If you have low ambient temperatures (both inside and out of your case) then you can probably get away with a performance profile without too much noise.<br><br>

Before we begin though, I'd like to briefly go over the tools we're going to be using to perfect these fan curves.<br><br><span style="text-decoration:underline;">Furmark Simulator:</span><br><a class="bbcode_url" href="http://www.ozone3d.net/benchmarks/fur/" target="_blank">Download Link</a><br><br>

By using custom settings in Furmark, we can simulate the temperatures of an extremely demanding game. These are the settings you should be using for all the tests below:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/900717/width/228/height/115/flags/"><img alt="115" class="bbcode_img lightbox-enabled" data-id="900717" data-type="61" src="http://www.overclock.net/content/type/61/id/900717/width/228/height/115" style="width:228px;height:115px;"></a><br><br>

Based on playing various demanding maxed-out games (The Witcher 2, Skyrim, BF3-Multiplayer, etc) I've tuned these settings to closely simulate the temperatures you'll see in these games but about 3C higher. This gives you some headroom if there's an especially demanding part of a game or benchmark that increases temperatures beyond normal levels.<br><br><b>Finding your idle Fan Speed:</b><br>

Now you need to find your idle temperature. To do this, be sure you don't have any benchmarks or videos open that might pull the card out of idle. Also be sure your have your stable overclock settings loaded and applied.<br><br>

First, set your fan to manually run at 25% by un-checking the Auto box and then moving the arrow on the side down until the fan read-out shows 25% and then click apply:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/900782/width/172/height/175/flags/"><img alt="175" class="bbcode_img lightbox-enabled" data-id="900782" data-type="61" src="http://www.overclock.net/content/type/61/id/900782/width/172/height/175" style="width:172px;height:175px;"></a><br>

You will need to wait 1-3 minutes for temperatures to stabilize. This resulting temperature is is your idle temperature. Now set the fan back to auto by re-checking the box, and then click apply. The reason we have to do this is because the manually-set fan speed minimum is only 25% and you might need to go lower than that to find your true idle fan speed. Open up the fan-curve editor and set a point 3C higher than your observed idle temperature and at 25% fan-speed. This is to account for ambient temperature variance. Now keep the X-axis set at your idle+3C temperature and reduce the fan speed in 5% increments (be sure to click 'OK' after each change and wait 1-2 minutes for temperatures to stabilize), until you see the temperature of your GPU increase by 1C. Be sure you don't go below 10% though. Now add 2% to this number and this is the fan speed required to maintain your idle temperature. For me, my idle temperature is 30C (so i set the X-axis at 33C), and i observed that at 10% fanspeed my temperature rose to a constant 31C, so i increased the fan-speed by 2% to 12%, and that's what i need to set for the Y-axis:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/900766/width/476/height/397/flags/"><img alt="397" class="bbcode_img lightbox-enabled" data-id="900766" data-type="61" src="http://www.overclock.net/content/type/61/id/900766/width/476/height/397" style="width:476px;height:397px;"></a><br><br>

The reason you want the fan speed to be constant at idle is so the noise profile is also constant. If you didn't have it at a constant speed, then when the fan has to increase even by as little as 1% it can change the noise profile slightly and with some louder fans (or fans that have frequent pitch changes) this can be noticeably annoying, especially when it oscillates by +/-1% constantly with each variance having a slightly different pitch.<br><br>

Now that you've set your Idle fan speed, you'll need to decide if you want to go with a quiet fan profile that might sacrifice some performance or a maximum performance fan profile.<br><br><b>Maximum Performance:</b>

<a class="spoiler-link H-spoiler-toggle" href="#"><strong>Warning: Spoiler!</strong> <span class="spoiler-help">(Click to show)</span></a><div class="spoiler-hidden">The objective of a maximum performance fan curve is to keep the GPU under the 70C throttle point at all times. If you have a non-reference card with improved cooling, this is the route you want to take. If you have a reference model and don't mind the louder fan profile and care more about performance than anything else, then this is also the route you want to take. However, the performance difference between this profile and the quiet profile will only be 13MHz (which is only about 0.5% performance difference), so it might be more practical to just go with the quieter profile below if you have a reference card or high ambient temperatures. The choice is yours.<br><br>

The first thing you want to do is manually set your fan to run at 85% (remember to hit apply). Then start-up a 'Burn-in' test with the custom Furmark settings. Wait about 4-5 minutes until the temperature read-out in the Hardware monitor stabilizes. I wouldn't suggest leaving your computer during this time because if you have very poor airflow or a hot card, you might hit some pretty hot temperatures. Just be ready to stop Furmark if you go over 84C. Now manually reduce (or increase) the fan speed a little bit at a time until you see the temperature stabilize at 69C. Keep in mind it's going to take about one minute after each fan change for the temperature to stabilize. Once you've found the fan percent you need to maintain a constant 69C, close Furmark. Now open the fan tab in Precision-X and add a point on the graph right at 69C and whatever fan percent you needed to stabilize Furmark at 69C. For me, i needed 79% so this is what my graph will look like:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/900730/width/475/height/394/flags/"><img alt="394" class="bbcode_img lightbox-enabled" data-id="900730" data-type="61" src="http://www.overclock.net/content/type/61/id/900730/width/475/height/394" style="width:475px;height:394px;"></a><br>

(notice the point is at 79% and 69C)<br><br>

Now set a second point at 79C and 100% fanspeed. This is really just a safety net in-case you ever do go over 69C to both protect your card from higher temperatures and to keep you well below the second throttle point at 79C.</div>

<br><b>Quiet Profile:</b>

<a class="spoiler-link H-spoiler-toggle" href="#"><strong>Warning: Spoiler!</strong> <span class="spoiler-help">(Click to show)</span></a><div class="spoiler-hidden">The objective of this profile is to reduce the noise of the fans to an acceptable level without sacrificing too much performance. The first thing you need to figure out is at what percent does your fan become annoyingly too loud for you to tolerate. To do this, manually set your fan at 50% and then increase it in 5% increments (remember to hit apply after each addition) until you get to a point that the fan noise is overbearing. Also pay attention for any annoying tone shifts. For example, if at 55% and 65% the fan sounds fine, but at 60% the fan makes a aggravating high-pitched squeal, then it might be best to completely skip that RPM when designing the fan curve. Here's an example:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/900799/width/477/height/396/flags/"><img alt="396" class="bbcode_img lightbox-enabled" data-id="900799" data-type="61" src="http://www.overclock.net/content/type/61/id/900799/width/477/height/396" style="width:477px;height:396px;"></a><br>

You see how it completely skips 60% and goes straight from 55% to 65%? There is one draw back to this though, and that is the temperature might get stuck at 55C oscillating between the two fan points. So you would hear the fans constantly shifting from 55% to 65%. You will need to decide if this fan throttling noise is better than the pitch change. If you're lucky, you'll be able to optimize this a bit and set the fan to jump from 58% to 62% and bypass the problem RPM's without having a noticeable fan throttling sound. You'll have to test that for yourself.<br><br>

Now that you've found the tolerable upper-limit of your fan, you're going to want to manually set the fan to run at that. Now start-up a 'Burn-in' test with the custom Furmark settings. Wait about 4-5 minutes until the temperature read-out in the Hardware monitor stabilizes. I wouldn't suggest leaving your computer during this time because if you have very poor airflow or a hot card, you might hit some pretty hot temperatures. Just be ready to stop Furmark if you go over 84C. While this test is running, closely watch the temperature read-out; if the temperature doesn't go over 69C at any point, then that means your GPU and fan setup is capable of running a maximum performance fan curve without being too loud. If that's the case, i suggest that you go up to the Maximum Performance fan section above and continue from there. If you go over 69C, then you will need to run a lower-performance (but quiet) fan curve. To do this, while the Burn-in test is running, manually increase or decrease your fan speed until the temperature read out stabilizes at 78C but never goes higher than that. Be sure you allow about 1 minute in between fan changes to ensure the temperature is truly stable. Now stop the Burn-in test and open the fan curve editor in Precision-X. You're going to want to place a point at 78C with the fan percent you just found. For example, for me i needed 62% to keep my GPU at a stable 78C during the Furmark test.<br><br>

Now set a second point at 82C with 100% fanspeed. This is just to protect your card from high temperatures, you should never actually go over 78C though.<br><br>

If you had any specific RPM ranges that produced an annoying sound range (like screeching or grinding), now is a good time to by-pass those areas like i showed above. You'll also need to decide if the additional fan throttling caused from by-passing those points is more desirable to listen to then the screeching/grinding.<br><br>

This is what your curve should look like:<br><a class="bbcode_url H-lightbox-open" href="http://www.overclock.net/content/type/61/id/900827/width/475/height/398/flags/"><img alt="398" class="bbcode_img lightbox-enabled" data-id="900827" data-type="61" src="http://www.overclock.net/content/type/61/id/900827/width/475/height/398" style="width:475px;height:398px;"></a></div>

<br><span style="font-size:9px;"><a class="bbcode_url" href="http://www.overclock.net/t/1265110/the-gtx-670-overclocking-master-guide#post_17391118">>>Link back to the table of contents<<</a></span>