Watercooling - highest efficiency PC builds?

j^aws

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Looking for recommendations, advice, pitfalls etc. for compact ATX/ mATX builds with SLI/ Crossfire setups with watercooling.

I've shortlisted the following two cases:

4960152.jpg

The above is a Thermaltake V21 cube design that's stackable as shown above It's an mATX case, so limited choice of boards. You can add radiators pretty much everywhere. Each cube is around mid-40 litres, so approx 80 litres stacked.
https://uk.thermaltake.com/core-v21.html

Image_21.jpg
Above is a Silverstone FT05, an ATX case, so more board choices. This case is also around 40 litres and is an inverted design layout. You can see two large fans intaking air and exhausting through the top.
https://www.silverstonetek.com/product.php?pid=522&area=en

Worst case scenario (no pun intended): 2x250 watt GPUs and 150 watt CPU, so around 650 watts to cool. Is it possible possible to get ultra quiet and cool temps with the above cases? What kind of kit would I need? Many thanks.
 
Id say for that amount of cooling your looking at a custom loop (an aio wont be enough)
(way beyond my expertise)
 
Looking for recommendations, advice, pitfalls etc. for compact ATX/ mATX builds with SLI/ Crossfire setups with watercooling.

I've shortlisted the following two cases:

View attachment 3500

The above is a Thermaltake V21 cube design that's stackable as shown above It's an mATX case, so limited choice of boards. You can add radiators pretty much everywhere. Each cube is around mid-40 litres, so approx 80 litres stacked.
https://uk.thermaltake.com/core-v21.html

View attachment 3501
Above is a Silverstone FT05, an ATX case, so more board choices. This case is also around 40 litres and is an inverted design layout. You can see two large fans intaking air and exhausting through the top.
https://www.silverstonetek.com/product.php?pid=522&area=en

Worst case scenario (no pun intended): 2x250 watt GPUs and 150 watt CPU, so around 650 watts to cool. Is it possible possible to get ultra quiet and cool temps with the above cases? What kind of kit would I need? Many thanks.
First off, what constitutes ”quiet” is entirely subjective, so using that as a parameter when asking strangers on the web for advice is a dicey proposition.

If we instead use the more stringent (although still subjective) ”silent” description then - no, you will not be able to cool such a system silently. At the end of the day you need to dissipate a certain amount of heat, and that will require a certain airflow, and depend on ambient air temperature. Note - if you run a system such you describe continously in a closed room, it will, in and off itself, gradually increase the ambient temperature to arguably uncomfortable levels (again subjective).

Simply put, dissipating large amounts of generated heat requires air convection, and a good bit of it, and the problem generally gets more difficult the smaller the enclosure. By my standards, a system such as you outline simply cannot be cooled quietly. But then I don’t live in the middle of a city, and my living space doesn’t have forced air circulation that creates a constant high noise floor. YMMV.

If you are hell bent on this kind of setup, I’d start with one GPU and as Davros suggests, use a custom water cooling setup that cools the GPU (and optionally the CPU too) and directly exhausts the air from the cabinet. Ideally though, you would prefer the pressure in the cabinet to be slightly higher than the ambient so that you can ensure that intake air gets filtered. So you would need quite capable fan solutions feeding the inside with cooler air that will be pushed through the radiator.

If you think that is quiet, and you feel that you need another 250W of GPU power, you can add that later and dial up the airflow and noise accordingly.
 
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^^ Some really good points, Entropy. And your username couldn't be more apt to describe heat exchange and thermodynamics!

So which components contribute most to the noise if I'm looking at a custom loop rather than an AIO solution? I'm thinking:

- Water pump make and model, where increasing pressure to increase water flow for better heat exchange generates more noise.
- Fan RPM, where increasing speeds increases air flow across radiators for better heat exchange and cooling at the expense of noise.
- Fan diameter, where for larger diameters a lower RPM is equivalent to the same air flow from a faster but smaller and noisier fan.
- Radiator fin density, where denser arrangements provide larger surface area for better heat transfer, but higher air resistance and noise from air flow through fins.

Anything else I've missed?

So, for the quietest builds, I'm looking at:

- Powerfull yet quiet water pump.
- Largest diameter fans.
- Fin radiator density for the required cooling - lowest required density.

The Thermaltake case with 2 stacked should be able to take 180/.200mm x 2 rads and large fans.

The Silverstone case will struggle with 180mm rads, but could look at smaller but thicker ones, maybe with top and bottom push/ pull fans.

What are the quietest water pumps?

For reference, what do you consider quiet for a complete build on standby and on full load in terms of decibels? I could hunt for videos to see if that kind of noise is acceptable to me.
 
Yeah, what would you possibly do with 2 3080 TI Super Titan FEs?
 
remember there are two types of fan
one optimised for cases and one optimised for radiators
you need one that prioritises static pressure over air flow.
https://graphicscardhub.com/best-static-pressure-fan/
That's a good reminder - forgot there are fans optimised for radiators.

ps: do you really want 2 gpu's ?

Yeah, what would you possibly do with 2 3080 TI Super Titan FEs?

You know it's kinda complicated. I had convinced myself that 1 GPU was the better value, but this build is more of a challenge to get the highest computation into the smallest volume whilst being quiet. Besides, with SLI/ Crossfire being on the downfall, the desirability for 2 GPUs for me is ironically higher. I still have a 3DFX Voodoo SLI setup for DOS/ Win98!

Another note, I'm hedging my bets that raytracing and the coming next generation will scale better with 2 GPUs, and maybe VR, too. These cases are meant to be cooling rigs, ready for extra power if required, so I'd probably start with 1 GPU and see how things pan out.
 
this is an interesting start to get into watercooling, something I've heard of but never tried myself.

Why are you interested in going SLI? Do you want to run games at 8k? Some games will work, but there are quite a few games that don't work with SLI properly and some only use the main GPU.
 
this is an interesting start to get into watercooling, something I've heard of but never tried myself.

Why are you interested in going SLI? Do you want to run games at 8k? Some games will work, but there are quite a few games that don't work with SLI properly and some only use the main GPU.
I'm not the biggest fan of resolution increases as I'd rather have more compute per pixel. So not that interested in 8k.

However, I have two builds in mind: A legacy XP build with SLI and a future raytracing/ VR build with SLI. The new consoles, and both Nvidia and AMD are committed to raytracing - we should see some developments over the next few years where GPUs would scale well with multiple configurations.

I'm expecting the next big benchmarking wars around RT!
 
Bet you never thought of anything like this when considering a compact, efficient water cooling solution for a PC build.
 
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