The Surface Laptop is Microsoft's latest foray into PC hardware, and reviews across the board have been overwhelmingly positive ... except for price considerations. If you noticed one consistency in those reviews it was the similar processor – Core i5-7200U with Intel HD620 graphics – that was tested. I was curious, however, about how the Core i7-7660U version stacked up regarding performance, battery life, and fan noise. Here is what I found.

Surface Laptop Core i7 performance comparison The Surface Laptop with Core i7 starts at $1,599, and it features 8GB of RAM and 256GB of storage, just like the specs in our Core i5 review unit. There is also an i7 version with 16GB of RAM and 512GB of storage for $2,199 that should be available on June 30. See at Microsoft Store The two main differences between the Core i5 and Core i7 are clock speed for turbo frequencies and the more powerful graphics with the Intel Iris Plus 640, both of which make the Core i7 well suited for power users. The cost difference is $300 between similar models for the extra RAM and storage. Part of that price difference is the Core i7, which has a suggested price of $415 versus the $281 for the Core i5. Best VPN providers 2020: Learn about ExpressVPN, NordVPN & more

Surface Laptop Core i5 vs. Core i7

Category Core i5-7200U Core i7-7660U Number of cores Two Two Number of threads Four Four TDP 15 W 15 W Base frequency 2.50 GHz 2.50 GHz Max turbo frequency 3.10 GHz 4.00 GHz Cache 3 MB SmartCache 4 MB SmartCache Graphics Intel HD 620 Intel Iris Plus 640

When it comes to graphics, the Iris Plus 640 has double the execution units – 48 – and features 64MB of eDRAM. The eDRAM is a big deal for performance and is completely lacking with the Intel HD 620. That eDRAM also is likely what drives up the cost of the chip because that memory is not cheap. Likewise, the Graphics Max Dynamic Frequency jumps from 1.00 GHz to 1.10 GHz with the Iris Plus 640. All of that effectively doubles the floating-point operations per second (FLOPS) from 384 to 730 in favor of Iris Plus. (Floating point operations are used for computing scientific or real-time processing applications that crunch extremely long numbers).

CPU GPU CPU & GPU SSD CPU Taking a closer look at Geekbench 4.0, which is more CPU-heavy than graphics-heavy, you can see a significant jump in performance between the Surface Laptop Core i7 over the Core i5 variant. Just as interesting is how the Surface Laptop's Core i7 slightly outperforms the Surface Pro (2017) with a similar configuration. That difference is likely due to more aggressive power throttling (more on that below). Geekbench 4.0 benchmarks (higher is better) Device CPU Single core Multi core Surface Laptop i7 i7-7660U 4,714 9,535 Surface Pro 2017 i7-7660U 4,513 9,346 Surface Book i7-6600U 3,977 7,486 Surface Laptop i5 i5-7200U 3,725 7,523 Surface Pro 4 i5-6300U 3,319 6,950 GPU While the Core i7 is faster than the Core i5, you see a bigger gap on the OpenCL test that looks at graphics performance. Geekbench 4.0 OpenCL (higher is better) Device GPU Compute score Surface Laptop i7 Iris 640 31,010 Surface Book GTX 965M 64,108 Surface Pro 2017 Iris 640 30,678 Surface Laptop i5 HD620 19,256 Surface Book HD520 18,197 Surface Pro 4 HD520 17,395 The Intel Iris Plus 640 (31,010) makes significant gains on the HD620 (19,256). While Iris Plus is not as powerful as a discrete GPU, it rivals the NVIDIA GT-940M (28,868), even beating it slightly. Nonetheless, for gaming, the discrete GPU will perform better overall due to greater memory and bandwidth – see, for example, how the Surface Book with Performance Base (GTX 965M) doubles the Iris Plus for OpenCL. For short, intensive tasks the Iris Plus is excellent, especially for productivity. CPU & GPU PCMark (Home Conventional 3.0) Device Score Comparison Surface Laptop i7 3,156 Better than 62 percent of all results Surface Pro 2017 i7 3,055 Better than 57 percent of all results Surface Laptop i5 2,494 Better than 40 percent of all results Again, for PCMark, the Surface Laptop with Core i7 beats all other mobile Surfaces including the similarly configured Surface Pro. SSD For those hoping the Core i7 version of the Surface Laptop would use a more powerful storage option, you will be disappointed. CrystalDiskMark (higher is better) Device Read Write Surface Laptop i7 486 MB/s 244 MB/s Surface Pro 2017 1,284 MB/s 963 MB/s Surface Book 1,018 MB/s 967 MB/s Surface Laptop i5 423 MB/s 237 MB/s Microsoft is using the same Toshiba (THNSN0256GTYA) solid-state drive (SSD) as the Core i5 variant at 256GB. It is not yet known if the 512GB Surface Laptop has a different drive, but since SSDs usually scale up in performance based on size, even if they're the same type, it should be faster than at 256GB.

Real-world usage for running apps, games, and the OS feels fast with the Surface Laptop's SSD, so it's not a problem unless you do large file transfers. Microsoft faced new constraints with the Surface Laptop because storage, for the first time, is directly integrated into the motherboard instead of a separate module. That choice was made to save space, power, and add a larger battery. The tradeoff seems worth it. Overall, there are no caveats or surprises here. The Surface Laptop with Core i7 outperforms the Core i5 version significantly for both CPU and GPU. The Laptop's higher scores compared to Surface Pro likely have to do with more agressive power limit throttling in the Pro due to its thinner and more compact chassis. Let's now turn to throttling to see what happens there. Surface Laptop Core i7 stress test and throttling CPU thermal management is always a challenge, so the question of whether Microsoft is purposefully limiting the Core i7 on the Surface Laptop is a legitimate one. To find an answer, I ran Intel XTU's stress test for 30 minutes on both the Core i5 and Core i7 Surface Laptops. Both power sliders were set to "Best Performance" with AC power to ensure the processors were maxing out. Microsoft is certainly not thermal throttling the Core i7 or Core i5, but there is some occasional power limit throttling. Power limit throttling (a.k.a. PL1) can be thought of as a skin temperature test that ensures the Surface does not get too hot to touch. It's dependent on the manufacturer – Microsoft – setting an upper limit on how hot the Surface (versus the processor) should be allowed to get before the system reduces the power draw, reducing overall CPU speed.

Thermal throttling, however, is a reaction to extreme CPU temperatures. Once the CPU hits an upper limit, it reduces power to lower the processor speed and drop temperatures. Likewise, processor thermal throttling can have severe oscillations in performance, whereas power limit throttling is more consistent. It is important to note that almost all laptops do this to some degree. PL1 is also the reason why some people use a USB fan to cool the back of the Surface Pro. The limit is entirely dependent on the room temperature and how hot the laptop gets. By cooling the outside of the Surface, you can stave off the effects of power-limit throttling. The result is the Core i7 running at 100 percent CPU usage in a room about 78 degrees F (26 degrees C) maintains between 3.2 GHz and 3.6 GHz, which is quite good. The Core i7 is rated for 15W TDP (but can turbo higher), and it fluctuated between 11W and 16W during the entire 30-minute test. Had I done the same test in a cooler, air-conditioned room, the results would have been even better due to the Surface Laptop chassis's ability to dissipate more heat efficiently. Heat and fan noise with the Surface Laptop Core i7 It should not be shocking to learn that the Surface Laptop runs hotter when configured with a Core i7 CPU versus the Core i5 model. Surface Laptop peak temperatures

Category Core i5-7200U Core i7-7660U Bottom of laptop 104° F / 40° C 113°F / 45° C Keyboard deck 102°F / 39° C 108° F / 42° C Exhaust vent 113° F / 45° C 120° F / 49° C

The Core i7 Surface Laptop gets significantly warmer on the aluminum bottom, keyboard deck and of course at the exhaust vent. While the temperatures were never extreme, the Core i7 after thirty minutes of 100 percent CPU usage – an unlikely scenario – pushes out more heat compared to the Core i5. While you may not want to use the Core i7 Surface Laptop while wearing shorts during a 30-minute stress test, at least under regular usage there is no significant difference between the two. Both laptops easily stay well below 100 degrees F (38 degrees C) and are comfortable to use.

For fan noise, the Core i7 is louder. While not as irritating as the Surface Pro 3 or Surface Pro 4's infamous "hiss," the fan was audible from three feet away during the 30-minute stress test. The Core i5 version, however, is still ridiculously quiet often requiring you to put your head near the exhaust just to hear it, even under load. In real world usage, both laptops are inaudible when browsing the web, using Windows Store apps, or doing productivity work. Even when under CPU load, like when playing a game or doing some light video editing, both laptops will be some of the quietest on the market. Nonetheless, if you value silence, the Core i5 version is an excellent choice because it almost seems fanless. Surface Laptop Core i7 battery life is great Testing battery life on a PC is rather difficult due to the extreme stepping technology that Intel uses, making it very task dependent. If running the processor at 100 percent you can run out of power in just a few hours. But that is not how most people use laptops. I did not find a radical difference in battery life with the Core i7 Surface Laptop compared to the Core i5 model. That result is likely because the type of computing I do – web browsing using Edge, writing in Microsoft Word, running Windows Store apps like Twitter, Adobe Photoshop Elements, Slack, and GroupMe – do not cause the i7 to run on the 4.00 GHz ceiling for long durations. For real-world usage, the Core i7 lasted me around eight hours, sometimes more, at 40 percent screen brightness and connected to Wi-Fi. Like the Core i5 version I never felt I had to carry the AC adapter – even if it's adorably small with this generation of hardware.

Microsoft claims 14.5 hours of life, but that is a looped video test with no network connectivity. Companies do this for one reason: it's a repeatable claim. Anyone can re-run that test and get the same result, whereas real-world usage varies widely by the user. Going to the other extreme is a run-down battery test like PCMark. That test, when set to accelerated, uses the CPU and GPU to continuously run looping tasks like photo editing, video chat, web browsing, and more, until the battery hits 20 percent. Here the results were surprising. With both displays set to 50 percent brightness and "recommended" for power usage, these are the results: PCMark 8 Home Battery Accelerated

Category Core i5-7200U Core i7-7660U Battery consumption Time Five hours and one minute Five hours and fifteen minutes 81 percent