Number of Rads

Palladan

Palladan

Palladan

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Joined
28 Jul 2016
Posts
41
Hi Guys,

I'm currently designing my first ever custom loop. I have a Fractal Design Define S case and love it. Except I don't want to take the top panels off for noise/dust reasons.

I'll be cooling an FX 9370, and 2x Sapphire Nitro+ OC RX 480's (Yes, full team Red which the theme will be based on)

The flow will be from pump - CPU - Rear Rad - GPUs - Front Rad - Resv.

Am I limiting the efficiency of the loop if I just have a 480 rad in the front and a 140 rad in the rear?

Thanks.
 
flow order doesn't really matter as the liquid will reach an equilibrium anyway after a short period of time and the rad space should be enough for your components.

rule of thumb 120 per item + 120 but more is better :D
 
Or look at the thermal figures for your stuff and pick a rad with the right wattage

here are hardware labs rad figures

GTS 120 - 300W - SO/DC/QC/GPU/
GTS 120 XFlow - 300W - SO/DC/QC/GPU/
GTS 240 - 700W - SO/DC/QC/GPU/SLI/CF
GTS 240 XFlow - 700W - SO/DC/QC/GPU/SLI/CF
GTS 360 - 1100W - SO/DC/QC/GPU/SLI/CF
GTS 360 XFlow - 1100W - SO/DC/QC/GPU/SLI/CF

GTX 120 - 420W - SO/DC/QC/GPU/SLI/CF
GTX 240 - 900W - SO/DC/QC/GPU/SLI/CF
GTX 360 - 1400W - SO/DC/QC/GPU/SLI/CF
GTX 480 - 1800W - SO/DC/QC/GPU/SLI/CF
 
archerz said:
flow order doesn't really matter as the liquid will reach an equilibrium anyway after a short period of time and the rad space should be enough for your components.

rule of thumb 120 per item + 120 but more is better :D
Click to expand...

OOPs ive got a 5820 and a titan and went for a 420,360,240 and 280 rad. Have I overdone it:? :p
 
archerz said:
are your temps in the minus figures ;) (obviously i know it doesnt work like that...)
Click to expand...

Ask me again in two days, I'm still piping the bloody thing up! :P

Aiming for no fans when browsing.

Ending up with 4700W of radiator cooling for a 250W gfx card and cpu :)

Of course I overclock to the extreme so those wattages can go out of the window.
 
Greebo said:
Aiming for no fans when browsing.
Click to expand...


I've got the same rad space as yourself, i can confirm you dont need fans on when browsing :), even light gaming. I have a few silent fans on one of the rads and tell it to kick in at a lower temp than the other rads, this makes sure all the other fans dont turn on when theyre not really needed. It makes a big dofference when your running 20+ fans.
 
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Thanks Sidewinder, Yeah, have been looking at that. It would be a 360 at the front. I was thinking about the floor fan mounting. My fear over placing a rad here would be drainage. I've been looking at the EK-KIT P360 as a basis of the build but want to add a drain port/solution and a thermometer in the loop as well. Maybe just an AF fan on the floor to help circulation.
 
A T-Fitting on the pump outlet would enable you to fit a drain port, there are also X-Fittings(4 way), which would mean you could add a G1/4 temp sensor as well.
Personally, I use a slim 420mm rad in the roof of the case, and find noise/dust isn't a problem, but I can understand wanting to keep the vents closed.
 
I'm using a 420 in the top and 280 in the front, for my PC, very happy so far. For adding a drain/temp sensor I am using one of these connected to the outlet on my res/pump combo


1 x Bitspower Q-Adapter 1/4 to 1/4 Inch 3x IG - Rotatable Carbon Black= £15.95

With it rotated so temp sensor is on top, drain comes out towards the edge of the case (unfortunately over my HDDs, but oh well), and a normal compression fitting on the end port going to my GPU.
 
BluD said:
I've got the same rad space as yourself, i can confirm you dont need fans on when browsing :), even light gaming. I have a few silent fans on one of the rads and tell it to kick in at a lower temp than the other rads, this makes sure all the other fans dont turn on when theyre not really needed. It makes a big dofference when your running 20+ fans.
Click to expand...

Will have my fans split from three hubs. Might set the to
Rad fans to come on low before the others as will draw heat from the whole case.
 
Yeah, thats how i did it, i have GT's on the top 480 which exhausts all the heat from the case, they come on first and will keep everything cool until i activate my overclock on the GPUs then the rest kick in once the GPUs get over 45 degrees and stops them going up any more.
 
Greebo - what's the temperature difference at the quoted wattages?

I work to roughly 0.06C/W per 120mm of radiator so I'd guess the 300W / 120mm works out at roughly twenty degrees. This strikes me as a bit hot for the air/water delta. Heat exchanged should be linear with surface area too, so the +100W for the very small gap between fans on multiple fan radiators looks optimistic.

Liking the fanless operation plan though. I only really got that working by mounting the radiators horizontally and that proved logistically difficult, so am sadly stuck on forced airflow :(
 
JonJ678 said:
Greebo - what's the temperature difference at the quoted wattages?

I work to roughly 0.06C/W per 120mm of radiator so I'd guess the 300W / 120mm works out at roughly twenty degrees. This strikes me as a bit hot for the air/water delta. Heat exchanged should be linear with surface area too, so the +100W for the very small gap between fans on multiple fan radiators looks optimistic.

Liking the fanless operation plan though. I only really got that working by mounting the radiators horizontally and that proved logistically difficult, so am sadly stuck on forced airflow :(
Click to expand...

I suspect they won't be great and will be maximums and also with fans at max speed. Saw a review of the 360 gtsI think at xtreme rigs and they tested it and it did indeed handle that kind of wattage so they had to admit the manufacturer wasn't lying. It worked out at 1090w so close enough. But they said that wasn't practical and just impressive sales blurb.

I wouldn't aim to use say a 500w rad to cool 500w of components though as like you said the water temp delta would be two high and the fans would be too noisy.

Will be interested to see what your estimate of my water delta would be based on my build? I'll be able to tell you this weekend :)
 
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Yeah the rads perform best at what theyre made for, some of them are for low RPM and will out perform most other rads from the 500-1000 rpm range, but then they suck at high rpm, and then there are some that are made for high rpm.

If you look at the Black Ice GTX gen 2 on the charts in the link below, at 750rpm push only it comes flat out last, but in push pull at 1800 rpm it comes first.

http://www.xtremerigs.net/2015/02/14/mayhems-havoc-360mm-radiator-review/5/

I remember i looked at some rads i had in the past and they were quoting like 1000 watts or summat but that was with 3k rpm fans, at 500 rpm how i ran them it was more like 120watts
 
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Well with my rads at 750rpm fans I'm probably good for 650w of heat disapated with a 10 degree water delta.

If I need more cooling then at 1300 rpm I'll have about 1200w and at 1850 rpm I'll have around 1700w for a 10 degree water delta.

So I'm not really expect my water temps to go much above 30c.

Fans at 750 rpm should give me decent enough cooling to even be overclocked and gaming (hopefully)

Full fan speed of 2200rpm to be used for benchmarking only. :)
 
I had mine setup passively but I didn't like the way warm air kinda stayed inside the case. (Enthoo primo 480 top and bottom) as there are other components in there that I guess need decent cooling... I have gone for a low tech solution of 4 fans sucking in through the bottom rad and 4 fans blowing out of the top rad constantly but at their slowest speed. Nigh on silent
No software control just nice and slow.

Max gaming temps are around 48°C on both th CPU and GPU.
 
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