Radiator size

FL630

FL630

FL630

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New to water-cooling and confused about radiator sizes.

What size would be the minimum I'd need for an overclocked i7-4790k and a EVGA GTX970 Superclock?

The case I'm looking at has space for a 280mm radiator, would this be enough?

Thanks.
 
Jony27 said:
For me is be looking at 360mm minimum,
What case are you looking at.
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NZXT Source 340.

It has 2 x 140mm fans on the top and the rear, I wonder if it could squeeze another 140mm rad somewhere up there too in exhaust?
 
Rule of thumb is 120mm for each components in the loop plus an extra 120mm, so for your i7 and 970 you would need 120 (i7) + 120 (970) + 120 = 360mm total.
 
Thanks NMBlack, never heard of that rule of thumb (and I've been googling all evening!)

Does cooling directly tally with radiator surface area?

A 360x120 rad gives 432cm^2 area and a 280x140 gives 392cm^2. Will that 40cm^2 make a huge difference?

Or are there other factors?
 
There's other factors like fpi and thickness. A low fpi thin 420mm rad may provide the same cooling ability as a thick high fpi 240mm but yes on the whole a greater area will tally with greater cooling ability.

While the rule of thumb is fine I prefer working out total tdp of components and then finding a rad that offers the dissipation ability needed.

Are you after performance or quiet? (Or mix?)
 
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You will be fine with a 280... When I had a leak in one of my rads I had sli 780's and an over clocked naked 3770 all running on a single 240mm rad. Low fpi (like 9 or so!) But the rad was 60mm thick... So little did it matter that I ran that setup until I broke a 780 as I never needed to add the 2nd rad back into the loop after repairing it.
 
Mynight said:
There's other factors like fpi and thickness. A low fpi thin 420mm rad may provide the same cooling ability as a thick high fpi 240mm but yes on the whole a greater area will tally with greater cooling ability.

While the rule of thumb is fine I prefer working out total tdp of components and then finding a rad that offers the dissipation ability needed.

Are you after performance or quiet? (Or mix?)
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Mostly quiet, I've never overclocked before so I suspect it'll be a tame OC on CPU only. I'm not a super heavy gamer either so I wont be stressing the GPU. A lot of the work I do is design and video editing (hence the i7) rather than maxed out gaming.

Due to case constraints, I think I'd be using a thin radiator, something like this: http://www.overclockers.co.uk/showproduct.php?prodid=WC-004-MA&groupid=962&catid=1523
 
Hmm, If you are planning on just using that magicool rad I would reconsider. Not that it isn't a good product but it is pretty thin. See if you can add a 120mm rad anywhere and that should be good. If you are planning on doing more CPU intensive work then i'd argue that that sort of work is much more intensive on your system (CPU running at 100% etc) than gaming. Last thing you want is to find out that the temps you have are minimal gain over air cooling. Plus if you were just running that one rad you would need some serious air pressure pumping through it which will mean silent operation is out of the question really.
 
I'm running an overclocked 4930K, SLI GTX970's and MB VRM/PCH blocks, cooled by a 360mm and a 160mm, 800 RPM fans speed controlled to ~600, temps and noise are great.
 
Thanks for the continued advice all.

Kipz said:
Hmm, If you are planning on just using that magicool rad I would reconsider. Not that it isn't a good product but it is pretty thin. See if you can add a 120mm rad anywhere and that should be good. If you are planning on doing more CPU intensive work then i'd argue that that sort of work is much more intensive on your system (CPU running at 100% etc) than gaming. Last thing you want is to find out that the temps you have are minimal gain over air cooling. Plus if you were just running that one rad you would need some serious air pressure pumping through it which will mean silent operation is out of the question really.
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I've actually changed case and direction of the build. I saw OC had a Bitfenix Prodigy in lime green in their B-Grade section for dirt cheap. Being a case I've always loved the look of I snapped it up.

This opens up the option of a roof mounted 240mm and a front 120mm, which is a good possibility.

Another option is the Phobya Extreme 200, which in theory gives me 400cm^2 at ~35mm deep. I'd have to get creative with HDD mounts but it would be a good solution I think. Looks a bit like this: http://i.imgur.com/DmXzq.jpg

Going to be modding the case before the build so hope to get a bit creative with the WC eventually :cool:
 
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A 280 will be fine in your situation as a 970 kicks out so little heat that it will cope just fine, you might find that your fans need running fast when benching but for gaming / rendering etc it will be fine. I went way over kill and have a single and a tripple in my loop but tbh the temp differences when taking the single out are not much and i even ran both on a single to see what would happen. It got warm in gaming (water hit 47c) but nothing got hot. However with the tripple and single i dont see water temps above 36-37c in gaming, a big res also helps
 
FL630 said:
New to water-cooling and confused about radiator sizes.

What size would be the minimum I'd need for an overclocked i7-4790k and a EVGA GTX970 Superclock?

The case I'm looking at has space for a 280mm radiator, would this be enough?

Thanks.
Click to expand...

General consensus is that you want 120mm fan space per main component (CPU and GPU's) plus a extra, (you can pretty much ignore heat added by motherboard waterblocks as being minimal).

So for CPU and 1 x GPU in a perfect world 360mm of radiator (1 x 360 or 1 x 120 and a 240 etc etc).

I have blocks on my CPU and 2 x GPUs, and motherboard VRMs and have a 480 and a 120 mm rad, so gone a little over what's needed.
 
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