Looking For Advice On First Water Build

Hi Guys,

just looking for some advice I've an MSI x570 mpg running a 3900x with 32Gig of Corsair Vengeance RGB PRO and an overclocked GTX 1070Ti.

GPU is on air and CPU is using a Corsair H115i 280mm AIO.

I am looking at a custom loop using Hydro X with a 360mm Radiator in the base and a 280 in the rear of my case,i could fit 2 360's but this way i dont loose both of my HD caddies.(if need be then i would i suppose 8TB is a bit much). I will be upgrading my GPU but not untill the next gen as i tend to upgrade every 3 generations or so and to be honest my 1070 is doing fine just now with a nice OC but the new one will be included in any loop obviously. I would like to start buying components pretty soon to try and spread the cost out a bit. As airflow has always been a major consideration in all PC builds I've done in the past Im trying to get my head around fan direction for this. The P120 only has fans on the bottom, side and rear so i would assume an intake for the 360 on the bottom but then would i better with exhaust on the side rad and rear fan or possibly both radiators as intake and exhaust on the 140 rear fan only? im just trying to think about any airflow for VRM's etc. As i say first time with a full water build and I'm just not sure how much air is required.

I've attached a not too great photo to let you see the fan config at present.

Thanks for any thoughts.

Popular thinking around here these days is that you are better off pulling cooler outside air in across your radiators, as opposed to pushing warmer inside air out through your rads. You generally get better cooling behaviour by utilising colder air across the rads. The air is generally going to find its way out of the case anyway, so finely balancing intake vs exhaust doesn't really seem as important as ensuring you make best use of cooler air.

Obvious statement - if you are pulling air in from the bottom, make sure you have adequate clearance under the case to get a supply of cooler air in there to suck in. I have a long haired shedding dog in my house and that approach wouldn't work for me, but your environment may be much more appropriate !

And if you can manage the above without having to lose your disk caddies, so much the better ;-)

Thanks for the reply,

thats kinda what i thought but its just getting my head round not obsesing qiute so much on through flow of air. my case has plenty space under it , the feet are about 35mm tall and my dogs are barred from my office :biggrin:. I'll maybe see how the cash goes with regards to the drives as i could fit a second nvme m.2 and another SSD and still remove the caddies.:laughing:

In full disclosure, I've completed exactly 1 watercooled build, so take what i say with a grain of salt. In my build I have 2 360 rads. One is mounted on the front where fans are pushing air into the case. The other one is mounted at the top where it pushes the air in the case out of the top.

The main "disadvantage" of this is that my top rad has to try to cool the coolant with air that has already been warmed by the first rad. Thermal efficiency would say it would be best to to either orient my top fans to also pull cold air in, or reorient my front fans to also push air out, drawing cool air in naturally from everywhere else. I considered this for a while and decided against it. The reason I decided against it is because it just wasn't worth it to me. Sure I could shave off a few degrees by reorienting some fans, but what do I lose in the process? Well, since I use ll120 RGB fans on the top, it simply wouldn't look as nice to turn those things around to pull air in. And if I switched my front fans, I'm now pulling air in from every other crevice in the case that doesn't have a filter on it...meaning I get more dust build-up more quickly. Some will argue that this doesn't matter, but after running air-cooled pcs for the last 5 years, I can tell you, those dust filters catch a lot.

So my whole point here is you need to evaluate what's important to you. For some people, they see this as a sport: to get every possible point of temperature measurement down as low as possible. And that's great! This is a hobby after all, solve for the thing that makes you the happiest. For me, watercooling has advantages in the aesthetics AND performance departments. So as long as my pc can allow me to overclock the hell out of my GPU, run quieter than a traditionally cooled pc, run significantly cooler than an air-cooled pc, keep temperatures in a respectable range, and look the way I want while doing it, that's perfect for me. The reason I'm bringing this up is there's a lot of enthusiasm out there for maximum thermal efficiency. I just want to voice that maximum thermal efficiency isn't always necessary, and it's totally ok to go with a design that isn't thermally perfect in order to achieve a certain aesthetic (within reason, of course...there are certainly objectively bad designs choices). Don't overthink it. Cheers, good luck, and have fun!

Good point ^^ that super duper thermal efficiency will be best served with fans at full blast anyway, so.. if you're not planning on tearing your ears off, having one rad as air intake and one as air exhaust is fine. You still have several fans exhausting warm air.

On the P120, you could very well run both rads as intake. It will make for a (very) positive pressure build that would, as a bonus, cool your power supply probably without needing it to ramp up fans.

That setup would have another advantage which is to have all your rad fans installed as pull, making cleaning the radiator fins very easy. And of course, positive pressure is traditionally cleaner when it comes to dust build up.

Experiment :)