Home PC Builds $5,000 Custom Loop Watercooled Gaming PC Build 2021!

$5,000 Custom Loop Watercooled Gaming PC Build 2021!

It's time for our first ever custom loop, water-cooled gaming PC build, featuring an ASUS STRIX RTX 3080 and AMD Ryzen 5 5900X!

Picture this: it’s a sunny, Spring day in the middle of April and GeekaWhat HQ is a hive of activity. The time has come, for the first time ever I’m going to be building a custom loop, watercooled gaming PC. The parts are together, the system spec changed last minute (in comes a Ryzen 9 5900X, out goes the i9 11900K) and a lot of expensive hardware is on the line.

In this build log, I’ll be detailing the whole process for our first ever watercooled system, looking at the parts we selected and taking a dive into performance. As well as sharing my experiences building my first custom loop, I’ll also be passing some advice over and sharing some handy resources.

Types of Loop

Before we look at all of the components used, it is worth noting that there are a few different types of watercooled systems. The first is a ‘soft tube’ system. This is on the easier end of the watercooled spectrum (though still relatively complex), and involves using soft, flexible tubing.

The other 2 ways of doing things are with ‘hardline’ tubing – often acrylic or glass. If you go the hard line route, you can opt to either bend the tubes to form your ideal runs, or use fittings to point the straight tubes in the right direction. It is most common for a hardline builder to bend at least some of the runs, using a heat gun and hardline bending kit.

I’ll be honest and admit that hardline was my initial choice, but following some advice to go for soft tubing first I eventually caved. Looking back, this was a good decision, as it keeps things a little more simple. You do of course still need to worry about forming your loop, fitting water blocks to a number of your components and a myriad of other things, but it keeps the heat gun at bay.

Advantages of Watercooling

The main question a novice might have when reading a piece like this is – why watercool? Why go to all the extra effort, and spend more money to run a liquid around a bunch of expensive electronics. The most agreeable answer is, because why not? If you want to max out price to performance metrics, then an AIO cooler is obviously the way to go for a high end build.

A custom loop, if done properly, will afford you a very quiet system though, and keeps temperatures more stable than any other setup. This is because you use the liquid to move the heat within your system, and can hook up an array of radiators (or just one if you want to keep things simple), to do all of the cooling leg work.

Liquid cooling is actually most common in server environments. In a space where increasing component density is key, while controlling temperatures, you can see why liquid cooling comes out on top. In server environments, the radiators don’t tend to be in the system itself as in our build, but I digress.

The Parts

Before you go any further picking out your favourite water cooling accessories, I’d recommend you get a balanced build thought out beforehand. It is important to have a base of solid, matched components in any build – but even more so here. A watercooled PC will keep temperatures low, but won’t transform a low power or bottlenecked system in any dramatic way.

CPU: Ryzen 9 5900X

As I alluded to earlier we swapped out the initial i9 choice last minute, in favour of AMDs Ryzen 9 5900X. If you really want to push the limits, the new 5950X is an even better option, but seemingly impossible to find at the moment. The 5900X with its 12 CPU cores and 24 CPU threads performs extremely well, while a boost clock speed pushing the 5GHz mark takes the single-threaded crown firmly away from Intel.

With a 105W TDP its also fairly power efficient, consuming around 20W less than Intel’s slower i9 11900K – a brand new CPU that actually has 4 less cores and 8 less threads.

Shop the Ryzen 9 5900X on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

GPU: Asus ROG Strix 3080

For the graphics card in my first custom loop, there was only one option in my mind – the ASUS ROG STRIX RTX 3080. The 3090 was off limits given its huge price premiums over the 3080 (for little extra by way of gaming performance), while AMD cards were also out of bounds through their lack of both Ray Tracing & DLSS.

The STRIX card has a great cooler, but we’ll be removing this later on to fit the GPU waterblock. It also has some boosted factory speeds, for a nice performance edge and a good rear IO, as is the case with most other 3080s out there.

GPU availability in 2021 is poor, and the situation doesn’t seem to be improving, but as I was lucky enough to have a 3080 to hand it made the most sense. Last gen cards like the 2080Ti are suffering the same issues on the used markets, and it is all just a big mess really. Either way, without putting too much of a downer on the piece, this is a phenomenal card… if you can buy one.

Shop the Asus ROG Strix 3080 on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

RAM: Corsair Dominator RGB 32GB

The memory for this build was a fairly simple choice, 32GB of Corsair’s Dominator Platinum SE provides a solid amount of RAM for all of our games and enough for the avid content creator. If you like a million and one chrome tabs then 64GB kits are also available. With Corsair’s awesome Cappellix RGB technology, the RAM lights up really bright, and looks fantastic with white heat spreaders and gold accents!

Shop Corsair Dominator RGB 32GB on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

SSD/Storage: Corsair MP600 Core

For the storage in this build, Corsair came in strong with their new MP600 Core. 2TB of super fast, PCI-E Gen 4 SSD make for a super fast system in every area. As you’ll see in the water cooling section, Corsair makes an SSD water cooling adapter which is ridiculous and awesome in equal measure. It will replace the otherwise buky built in heatsink, though, which is a bonus.

Corsair makes an SSD water cooling adapter which is ridiculous and awesome in equal measure.

Shop Corsair MP600 Core on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

Keep scrolling for the rest of the components, but remember: we’ve uploaded a video version of this build below!

Motherboard: NZXT N7 B550

The motherboard choice might seem a little odd at first glance, as we’ve opted to go for the new NZXT N7 B550 motherboard. Yes, a B550 board. AMD seem to have managed to make the older B450 and X570 chipsets redundant in one foul swoop (at least in my view), with B550. Support for fast Gen 4 SSDs (something we’ll be taking advantage of soon), CPU & RAM overclocking and plenty of expandability and it is top marks all around!

Shop NZXT N7 B550 on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

Case & Fans: Corsair ICUE 5000X RGB

Corsair ICUE 5000X RGB

Corsair QL 120 RGB

For a custom loop gaming PC, you need to pick up a case big enough to handle all of the extra water cooling gear that you wouldn’t normally need to consider. The Corsair iCUE 5000X is our choice, and we learnt throughout the process how much smaller cases feel when you watercool in them. In any other build the iCUE 5000X is a colossal, full PC tower that can swallow up any hardware. This is case that makes a 320mm+ GPU feel small, but got quickly filled up by our water cooling gear.

To be fair, we did opt for two 360mm radiators, an overkill setup by most people’s standards, 13 (!!) 120mm RGB fans and used the side-on radiator mount. This wasn’t without one or two hiccups along the way, but the system looks fantastic and extra effort was well worth it. If you’re looking for a slightly simpler build, then ditch the side-on radiator mount. This will give you more breathing room up front for a push pull radiator, more wiggle room for a reservoir and overall a more spaced out build.

Shop Corsair ICUE 5000X RGB on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

Shop Corsair QL 120 RGB on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

the system looks fantastic and extra effort was well worth it.

PSU: Corsair RM850x

Yes, it is a little boring compared to the RGB CPU water cooling waterblock, but it is super important. The component we’re talking about is of course the power supply. For an RTX 3080 build you want to opt for a 750W power supply or above to make sure you don’t fall foul to the odd GPU power surge wiping out a 650-powered system. With a watercooled system, you’re also likely to have lots of SATA or Molex power cables that need plugging in, so a beefed up unit is a better choice

The Corsair RM850x is a fantastic power supply choice, with a fully modular interface, a white model available and included braided cables. It adds to the build aesthetic here, and works really well with the white 5000X chassis!

Shop Corsair RM850x on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

Watercooling Gear

To watercool this system we need a few core components, which will form our basic loop.

CPU & GPU Water Block:

Corsair Hydro Series XC7 RGB White

Corsair Hydro Series XG7 RGB

The first of those is a waterblock for the processor or graphics (or indeed both). This is what our coolant flows through, to cool down the chips. Essentially there are machined fins in the block, made out of a good heat conducting surface – which allow for the transfer of heat from the processor to the coolant (and visa versa).

We also need some coolant, the liquid which actually flows through all of the watercooling gear. There are plenty of cool options out there, including coloured options which really set a build off. These more complicated coolants, from the likes of Mayhems, do increase complexity into a build and may require more maintenance. We opted to keep it simple, with a clear coolant free of colourings or other modifications. This choice will allow us keep our build fairly low maintenance, which is important to me.

Shop Corsair XC7 RGB White on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

Shop Corsair XG7 RGB on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

Water Cooling Radiator: Corsair XR5 360

Radiators are next up, the key component which allows the liquid to be cooled down. We opted for two 360mm radiators, each capable of mounting 3 or 6 fans to push air through the fin array. This might seem overkill, but cooling a powerful CPU and GPU in one loop introduces lots of heat – so better safe than sorry! You’ll see this decision pay off later in our system temperature testing.

Shop Corsair XR5 360 on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

M.2 SSD Water Block: Corsair XM2

The final notable component in this system is the power supply – specifically we’ve selected the Cooler Master MWE650 Gold. It is a really nice power supply, with a fully modular interface, high efficiency rating and quiet operation.

650W is the perfect amount for a system of this spec, but we wouldn’t recommend dropping this down with the aim of saving cash. Avoid the headache with an efficient 650W unit!

Shop Corsair XM2 on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

Pump/Reservoir Combo: Corsair XD5 RGB White

We also need a reservoir and pump for our liquid cooling system, to store and fill our loop up, and to pump the liquid around the system. We used the online Corsair Hydro X configuration tool to spec our loop, and Corsair’s own XD5 pump and res combo seemed like a solid choice. Aesthetically the more squared off reservoir is a more modern take on the cylinder design, while the pump is powerful enough to move the liquid around the whole system today!

Shop Corsair XD5 RGB White on Amazon (US) / Amazon (UK) / Amazon (Intl.) / Ebuyer (UK)

Finally, the last few bits we need to fulfill our watercooled dreams are some tubing and fittings. The tubing will run to each of our components, to form the loop the water flows around, while fittings allow us to connect the tubing up. For our build we opted fr a combination of right angle, 90 degree fittings and 45 degree fittings. Both of these were rotary designs, allowing us to spin the direction of the 45 or 90 degree angle.

Compression fittings round off the connectors, with these being the most important of all the fittings today. These compress around the soft tubing, and hold it into place. These make sure you avoid leaks or disconnects, so safe to say that they’re pretty important!

As alluded to above, we used Corsair’s fantastic Hydro X configuration tool for this. The site allows you to enter in your motherboard and graphics card choices, and even add non Corsair chassis in to find the perfect water cooling options. For a liquid cooling novice, like me, it is a superb tool!

Extra fittings are handy for giving you flexibility in this and other areas of the build – allowing you to route tubes into harder to reach locations. They can be pricey, and I see why people don’t want to buy too many, but they are super handy. Especially when you remember that you can pair up a 45 degree and 90 degree fitting here and there to get a better run.

Fittings become more important in a hardline build, especially if you’re trying to limit heat bending. The location and direction of the fittings really seem to dictate the liquid cooling runs you make, so use this to your advantage!

Performance & Benchmarking

Awesome stuff – we’ve covered off all the parts in our system and its now time to run some games, about 15 to be precise, to see what kind of performance figures we’re able to achieve! At 1440p high settings the numbers the numbers looked good, while 1080p is an ever better story – predictable.

Games tested include: Apex Legends, COD Cold War, COD Warzone, Control, CS:GO, Cyberpunk 2077, Death Stranding, Fortnite, GTA V, Rainbow Six Siege, Valorant, Watch Dogs: Legion & Overwatch!

Apex Legends144 FPS
Valorant328 FPS
Fortnite164 FPS
Overwatch212 FPS
Tested at 4K High Settings
Watch Dogs Legion85 FPS
COD Black Ops Cold War97 FPS
Cyberpunk 207757 FPS
Death Stranding94 FPS
Control70 FPS
Rainbow Six Siege220 FPS
Tested at 4K High Settings

Make sure to get subscribed to our dedicated benchmarking & build channels, using the buttons below to get notified whenever we publish a new build!

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Performance aside, one super important factor with any build is how it looks …right?! This build is a bit of a stunner if I do say so myself, and below is a gallery of some of the awesome stills we pulled from this system – take a look!

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