[Q] Radiator Size Discussion

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TheHobbyist

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Hello,

I am interested in water cooling a 4770k and either two 780's or two Titans (All Overclocked). According to the [H] reviews, the 4770k overclocked to 4.8ghz leads to a system usage of 183 watts under load. Also, the 780 overclocked uses about 360W. The Titan overclocked uses about 406W (correct me if I'm wrong on this one).

So we have:
4770k 183W
780 360W
780 360W
Total: 903W

or

4770k 183W
Titan 406W
Titan 406W
Total: 995W

According to the [H] water cooling sticky, the rule of thumb is to divide total wattage by 150 and then multiply that number by 120 to determine the amount of surface area needed. Unfortunately, the link given for a more detailed explanation is no longer active (http://www.over-clock.co.uk/ivb/index.php?showtopic=20277).

Using this rule we have:

903W/150 = 6.02 x 120 = (720)

and

995W/150 = 6.63 x 120 = (840) 796

I have read that a 10 degree water delta is what you should aim for. What are your experiences?

I would like to use GT AP-15's or equivalent at about 1000-1200 rpm in a push configuration. So what do you guys think? Does this setup require 720-840mm of radiator? Is there a more accurate way to calculate required radiator space?

Thanks
 
W.Feather said:
http://www.pcper.com/reviews/Cases-...-Radiator-Comparison-Thickness-vs-Fin-Density

just ran across that the other dya, looks interesting i still need to get into it


However as for your question --- you would need atleast a 480mm radiator (thats one with room for 4x 120mm fans per side), IMO, if not a little more cooling space to keep the temps down to where I would want my equipment under water to be at.
Click to expand...

Thank you for the reply. Does anyone else have any input regarding this matter? Thanks
 
I went with 240x120mm (2 fans) per high end component. I did this purposely for the sake of being able to run things low and quiet with excellent cooling. My goal was high OC with near silence. I also used a fat radiator XSPC RX480 (which i highly recommend if you can fit it) to cool a voltage hungry 5.0ghz 2500k and a flashed HD6950. GPU stays stone cold...CPU will hit 90 under IBT with AVX at 1.53v. Playing games like BF3 i might see mid 60's on my CPU.
 
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nissanztt90 said:
I went with 240x120mm (2 fans) per high end component. I did this purposely for the sake of being able to run things low and quiet with excellent cooling. My goal was high OC with near silence. I also used a fat radiator XSPC RX480 (which i highly recommend if you can fit it) to cool a voltage hungry 5.0ghz 2500k and a flashed HD6950. GPU stays stone cold...CPU will hit 90 under IBT with AVX at 1.53v. Playing games like BF3 i might see mid 60's on my CPU.
Click to expand...

Thanks for your input! What is your water delta? (how much hotter is the water in your system compared to the ambient temperature?) Do you use push or push/pull with your fans? What rpm do you run your fans at?

Great feedback guys, do anyone else care to chime in?

Thanks!
 
Cant say what my water delta is dont have anything to measure it but based on what im cooling im estimating in the 5-10 degree range. My fans are in pull, and draw in fresh air from the bottom side of my case (TJ-07, RX480 mounted in the bottom. I have a pic somewhere around here ill see if i can find it. Fans are run around 1000rpms.

Pic is older and crappier than i thought. http://img261.imageshack.us/img261/5356/95915615.jpg You can see the rad mounted in the bottom though. That particular setup is a GTX260 oc'ed with a 4.2ghz Q9650, also ran dead silent.
 
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nissanztt90 said:
Cant say what my water delta is dont have anything to measure it but based on what im cooling im estimating in the 5-10 degree range. My fans are in pull, and draw in fresh air from the bottom side of my case (TJ-07, RX480 mounted in the bottom. I have a pic somewhere around here ill see if i can find it. Fans are run around 1000rpms.

Pic is older and crappier than i thought. http://img261.imageshack.us/img261/5356/95915615.jpg You can see the rad mounted in the bottom though. That particular setup is a GTX260 oc'ed with a 4.2ghz Q9650, also ran dead silent.
Click to expand...

I've got a very similar setup but with 2 240mm rads but no way to read water temps either. Cause honestly I don't really care about water temp. I know i have tons of rad for my setup, and due to that i can run the fans nice and slow too. I think mine idle at 900 and can spin up to 1400 if it gets uber hot. The GT's are very quiet at 900.

OP, I'd say in terms of cooling that much hardware, I'd suggest at least 2 360mm rads or as much as you can easily handle inside or outside the case. The more you have the slower your fans can run.
 
Imitation said:
Cause honestly I don't really care about water temp. I know i have tons of rad for my setup, and due to that i can run the fans nice and slow too. I think mine idle at 900 and can spin up to 1400 if it gets uber hot. The GT's are very quiet at 900.
Click to expand...

Pretty much my sentiments exactly. 900 to 1400rpm in fan speed isnt really going to have a significant impact on OCing, especially when you use a nice fat radiator with lower-ish fin density. If you want the best cooling with silence your best bet is to go with as much radiator area as possible. Surface area for heat exchange is key. A thin cheap swiftech rad setup with 600x120 to perform better than a fat RX480 (480x120), but then you need to start taking flow into consideration, youll want a solid strong pump like the D5 for that. I would still recommend the RX series over the swiftech if you can afford it and fit it, i have just been thoroughly impressive with this thing over and over. The swiftech series is still huge bang for buck though.
 
My buddy has a very similar rig to what you are proposing. He used 2 rads one 360mm top and a fat 240mm bottom and cools an overclocked 3770 @ 4.9ghz with a gtx 680 no problem. I can't remember his temps exactly but I wanna say under full load cpu doesn't get above 50c and the gpu 45-50c. I would go against a push pull configuration for the simple fact the push fans blow dust on the rads and clog them up. I would run just pull with some high pressure fans with good gaskets that seal the fan to the rad. You might get a few degrees lower temp with a push pull (some say it doesn't help much) but I would rather not have to worry about my rads filling up with dust. Just my 2 cents good luck with the build!
 
Push/pull is rather redundant and seals are extraneous. Also a 3770 at 4.9 is going to push into the 80's even with good water cooling at full load. Gaming wont push it higher than 50's or into the 60's in a CPU intensive game.
 
W.Feather said:
http://www.pcper.com/reviews/Cases-...-Radiator-Comparison-Thickness-vs-Fin-Density

just ran across that the other dya, looks interesting i still need to get into it


However as for your question --- you would need atleast a 480mm radiator (thats one with room for 4x 120mm fans per side), IMO, if not a little more cooling space to keep the temps down to where I would want my equipment under water to be at.
Click to expand...

Martin's Liquid Lab gives you a better idea of what happens across various radiators, as not all radiators are built equally.

In general, low FPI are favored by low RPM fans, while high FPI radiators are favored by high RPM fans. Extra thickness favor all fans in general, unless you're down in the 600 RPM range, where thickness above 45mm can be detrimental to performance (as shown by the XT45 and UT60 comparisons).
 
nissanztt90 said:
Cant say what my water delta is dont have anything to measure it but based on what im cooling im estimating in the 5-10 degree range. My fans are in pull, and draw in fresh air from the bottom side of my case (TJ-07, RX480 mounted in the bottom. I have a pic somewhere around here ill see if i can find it. Fans are run around 1000rpms.

Pic is older and crappier than i thought. http://img261.imageshack.us/img261/5356/95915615.jpg You can see the rad mounted in the bottom though. That particular setup is a GTX260 oc'ed with a 4.2ghz Q9650, also ran dead silent.
Click to expand...

That RX480 is a beefy radiator =) 1000rpm fans with excellent temps is simply bliss! :D

Imitation said:
I've got a very similar setup but with 2 240mm rads but no way to read water temps either. Cause honestly I don't really care about water temp. I know i have tons of rad for my setup, and due to that i can run the fans nice and slow too. I think mine idle at 900 and can spin up to 1400 if it gets uber hot. The GT's are very quiet at 900.

OP, I'd say in terms of cooling that much hardware, I'd suggest at least 2 360mm rads or as much as you can easily handle inside or outside the case. The more you have the slower your fans can run.
Click to expand...

Thanks for the feedback! So you recommend about 720mm of radiator then for cool and quiet! I am defiantly all about slow and quiet fans with great temps.

nissanztt90 said:
Pretty much my sentiments exactly. 900 to 1400rpm in fan speed isnt really going to have a significant impact on OCing, especially when you use a nice fat radiator with lower-ish fin density. If you want the best cooling with silence your best bet is to go with as much radiator area as possible. Surface area for heat exchange is key. A thin cheap swiftech rad setup with 600x120 to perform better than a fat RX480 (480x120), but then you need to start taking flow into consideration, youll want a solid strong pump like the D5 for that. I would still recommend the RX series over the swiftech if you can afford it and fit it, i have just been thoroughly impressive with this thing over and over. The swiftech series is still huge bang for buck though.
Click to expand...

Thanks for the tips on radiator selection! I agree that surface area is key when it comes to water cooling!

drklu said:
My buddy has a very similar rig to what you are proposing. He used 2 rads one 360mm top and a fat 240mm bottom and cools an overclocked 3770 @ 4.9ghz with a gtx 680 no problem. I can't remember his temps exactly but I wanna say under full load cpu doesn't get above 50c and the gpu 45-50c. I would go against a push pull configuration for the simple fact the push fans blow dust on the rads and clog them up. I would run just pull with some high pressure fans with good gaskets that seal the fan to the rad. You might get a few degrees lower temp with a push pull (some say it doesn't help much) but I would rather not have to worry about my rads filling up with dust. Just my 2 cents good luck with the build!
Click to expand...

I appreciate your 2 cents drklu! I also agree that push/pull doesnt help much (at least from my own experiences and from what I have read at Martin's Liquid Lab). Dust in the radiators in no bueno.

nissanztt90 said:
Push/pull is rather redundant and seals are extraneous. Also a 3770 at 4.9 is going to push into the 80's even with good water cooling at full load. Gaming wont push it higher than 50's or into the 60's in a CPU intensive game.
Click to expand...

You bring up a good point nissanztt90: with the exception of benchmarking and stress testing, there is going to be a lot less heat in the system. I am personally only concerned with day to day usage. Also, it is true that there is definitely a ceiling on the 3770k and the 4770k processors! Some of that can be alleviated with de-lidding, but there is definitely a glass ceiling just due to the silicon.

Tsumi said:
Martin's Liquid Lab gives you a better idea of what happens across various radiators, as not all radiators are built equally.

In general, low FPI are favored by low RPM fans, while high FPI radiators are favored by high RPM fans. Extra thickness favor all fans in general, unless you're down in the 600 RPM range, where thickness above 45mm can be detrimental to performance (as shown by the XT45 and UT60 comparisons).
Click to expand...

Thanks for the feedback Tsumi :)

Martin's Liquid Lab is an awesome resource! I agree with what you have said. I am personally interested in fan speeds in the <1400rpm range.
 
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