Water Blocks

A water block is a heat spreader hidden in a (typically) acrylic body. One side of a heat spreader touches a die with its polished cold plate, while the opposite side provides a stack of microchannels that contact a coolant. These microchannels save the same purpose as radiator fins — they enlarge the contact surface area to accelerate the heat transfer.

The overall construction is pretty straightforward with no moving mechanical parts or high- tech production requirements, which makes waterblocks probably the best candidates to save a few bucks on.

CPU Blocks

Speaking of CPU waterblock, buy whichever fits your motherboard socket. Modern blocks have adaptable mounting brackets for almost all existing Intel and AMD sockets. Some blocks, like Supremacy EVO from EK Waterblocks, may require quick customization since they ship with several inserts and jet plates enclosed and depending on your processor you may need to replace the ones which are factory-installed. Just read the installation manual that comes with your block and this procedure should not pose any difficulties.

GPU Blocks

With GPU blocks things get more complicated because of different card manufacturers have different board designs. The key word here is “reference.” Be careful — it does not mean the same thing it used to a few years ago. I’m going to use NVidia cards as an example, but same applies to AMD products as well.

A “founders edition” design is a PCB of NVidia’s Founders Edition (FE) cards. These are cards manufactured directly by NVidia (or copied entirely by their partners) and have NVidia-designed blower coolers.

A reference design is a PCB design developed by NVidia for their partners (Asus, Gigabyte, MSI, Zotac, etc.). These 3rd-party manufacturers clone the NVidia’s reference PCBs and attach their cooling solutions, colored shrouds, RGB LEDs, etc.

FE and reference designs are not the same and may feature different board elements’ layouts and\or back I\O panels.

For example, this is the compatibility list for the EK-FC1080 GTX Ti water block. Note that many 1080 Ti cards with a reference board design (like Inno3D 1080Ti X3 or EVGA 1080Ti SC2 Gaming) are missing from this list. It means the “FC1080 Ti” block is compatible with Founders Edition cards only, whereas for reference design card you need to buy the EK-FC GeForce GTX FE block instead (which, ironically, has the “FE” in its name while the actual FE-compatible block does not). I personally contacted EKWB with this question, and the answer was that the FC1080 block MAY fit a reference card not listed among supported ones, but you have to try it at your own risk.

Custom (non-reference) cards manufactured by NVidia’s partners feature both custom coolers and reworked PCBs. Major waterblock manufacturers offer blocks that exclusively support specific card brands. For example, the FC1080 G1 block is designed for top-tier Gigabyte G1 cards, the FC1080 Aorus block also supports Gigabyte cards (but those of the Aorus model line only), and the FC1080 TF6 block fits MSI graphics cards.

Manufacturers need to receive a sample card from GPU makers and research it before they can start developing a compatible plate, so blocks for non-reference GPUs are typically unavailable for some time past a card release. What’s worse is that some non-reference cards have no full-cover blocks that fit them, at all. For instance, the FC1080 Strix block supports cards from the Asus Strix line, including 1070 cards. However, an Asus 1070 Dual card is not compatible with this block. And since it has a non-reference PCB, reference blocks won’t do either. Plan a loop long before you start picking its actual parts: be sure you will be able to get a block for a GPU you’re buying.

Reference VS aftermarket GPUs

Many first-time builders are confused whether they should get a top-tier after-market card “A” or a cheaper reference card “B.” Given that you found full-cover blocks for both cards, the question is not that simple. Buying card “B” seems more reasonable at first sight, since both cards have identical GPU dies and memory chips and the majority of an aftermarket card “A”s price is its custom cooler (which you are going to replace with a waterblock anyway). However, aftermarket cards can have separate minor advantages that make them a viable choice.

Reworked power phases may boast better performance and push the overclocking potential a bit higher.

More expensive VRMs and capacitors are more likely to last longer if you are continually subjecting your card to extreme load levels.

Onboard fan connectors in Asus Strix cards allow you to monitor fan speeds based on GPU temps without employing third-party software like Speedfan.

Finally, a good-looking and well-built stock backplate can spare you from buying a separate one (given that it is compatible with the installed waterblock).

The choice is yours to make; purchasing an expensive aftermarket card for water-cooling is not necessarily a waste of money as many do believe.

Universal GPU blocks

A few paragraphs ago I mentioned that you might be unable to find a “full-cover” block for a non-reference card. Some people believe that a “full-cover” block is a block that stretches along the entire board. This is not quite right, the FC1080 TF6 block leaves both sides of MSI cards’ boards open, but it’s still a full-cover waterblock. A full-cover block touches a GPU die, memory chips, and VRMs. As opposed to that, a universal block cools the GPU die only. It is quite evident that universal blocks are less efficient and require additional air cooling for card VRM zones. You should buy these blocks only if you’ve purchased a GPU before planning to build a water cooling loop and found out there’re no full-cover blocks for your card.

Backplates

Most modern cards have stock backplates that increase the card durability and somewhat help with cooling board VRM sections. If you can mount a stock backplate back onto the card after installing a waterblock (e.g., the FC1080 TF6 block mentioned above is compatible with stock MSI 10x0 Gaming card backplates) — excellent. If not, you may buy a replacement from the same water cooling manufacturer. A waterblock filled with a coolant adds a lot of weight to your card, so having a backplate as an additional reinforcement is nice. So is a minor VRM cooling. But for me, both of these are not principal backplate advantages. What’s most important, you get decent leak protection: the GPU stretches across the entire case, and if a leak forms somewhere in the upper part of a loop, an unprotected GPU has very high chances to get soaked and fried. And secondly, a proper backplate adds a lot of sexiness to your build. And don’t even bother saying that it’s not a relevant factor to you! :)

RAM Blocks, Motherboard Blocks, and Others

Nowadays you can water-cool almost every part of your PC: RAM sticks, motherboard VRMs, disk drives, M.2 sticks — you name it. Doing that is optional, most of these parts are very durable and designed with operating at high temps in mind. For instance, Corsair gives ten years warranty for their overclocked memory sticks — they wouldn’t do that with fragile hardware, right?

Most vulnerable parts among all of these are, probably, motherboard capacitors. Manufacturers only state how many hours will these capacitors endure at a particular temperature, e.g., 5 years at 130 degrees Celcius. Operating at higher temps burns through capacitors’ lifespan and water-cooling them might be reasonable. And it does not necessarily mean you need to buy an additional piece of equipment: many vendors offer MB blocks combined with regular CPU blocks into something called “a monoblock.” Like the EK block for the Asus Rampage V Extreme board.

This bad boy has multiple cold plates to touch a CPU, a PCH, VRMs, MOSFETs — anything that gets hot under heavy loads. Which means if you get a monoblock, you don’t need a regular CPU block anymore.

But, to quote John Constantine, “there’s always a catch” — same as graphics cards, motherboards have unique element layouts. And for that reason, you cannot get a “universal monoblock” that would fit any board, as it would work with a simple CPU block. Instead, you will need to (again!) do some research looking for those blocks that are compatible with your specific hardware.

If you decide to include additional water blocks in a loop, remember that every one of them increases the coolant temperature and the overall resistance that reduces the fluid head pressure. To neutralize that, you will need to enlarge the radiators’ surface area and ramp up the pump a bit higher.