SOLVED Tell me how much cooling/radiator I need for my prospective build...

First post from a new member and a WC noob! Greetings!

Here is the hardware I am planning on:

MOBO/CPU- i7-4790k on a Maximus 6 Impact with full board cooling by EK

VGA - EVGA 780 GTX Ti with full board cooling by EK

RAM - 16G Corsair Dominator cooled by EK Monarch

Power- EVGA SuperNova 850, EVGA 1200 or a Corsair Ax860i (I've heard some bad things about the 860i, but I'm not sure if they are true or not)

NexXxos Monsta 140.2 and 140.1 or 120.3 and 120.1 in a CaseLabs Mercury S3 or S5

Koolance 800W chiller

1- EK Single 5.25" Bay Reservoir w/ Dual Serial DDC 3.2 PWM Pumps

1- Alphacool dual bay res with 1-4 MCP35x

6- Noctua Industrial NF-A14 140 x 25mm IP67 PWM Fan

My plan was to have the chiller feed the small res, then the big one, and it feeds both the MOBO/RAM and the GPU separately (paralell loops). I was not planning on overclocking until I saw what my temps were at...

Too few rads? Should I not put the 140.2 rad above the res pair? Any thoughts on the Ax860i?

Thanks for your help and input!

Chillers work against radiators. If the chiller doesn't bring the water temp below ambient air temp then it's pointless(because it's dead easy to get water within 5℃ of the air temp) and if it does bring the water temp below ambient air temp then the radiators will heat the water rather than cool it.

+1

Chiller with Rads = FAIL

just return water to the chiller , use as small of res as possible simply a place to fill the loop, you will need to use a gloycol solution in the loop to keep it from freezing up.

Now if you need a rad with no chiller I would go with 120.5 (which ever config triple n dual or quad and single) dont know how that would configure in your case or the equivalent in the 140 rad or monsta

to OCFs.

Supertrucker said:

Chillers work against radiators. If the chiller doesn't bring the water temp below ambient air temp then it's pointless(because it's dead easy to get water within 5℃ of the air temp) and if it does bring the water temp below ambient air temp then the radiators will heat the water rather than cool it.

Click to expand...

+1

You'll need to figure out if you want to go with a chiller which will result in insulating your gear for condensation or go full custom water cooling. I am not too familiar what else involves with chilling but will leave this to the chiller experts and if you decide to go custom water cooling and new to it all, take your time and read our yellow water cooling stickies in this section of the threads up top.

Thanks for your input.

Please help me understand- I was gonna use the rads to lower the coolant temps (esp. if I overclock) so that the chiller didn't have to work so hard. Is that still a viable thing to do, or should I just go either the chiller route, or rads and pumps? And since I was gonna lock the coolant temps to -5 from ambient, I'm not too worried about condensation, but it's always good to be prepared...

Again, thanks for educating me...

What they are saying is that if you have the water chilled to -5c from ambient temps as soon as it goes into the rad it will warm it back up to ambient that what rads do. The water coming from your CPU block isn't hot, it's barely warmer than the water going in. so if it goes in at 15c it comes out at 15.2c but when it hits the radiator in a 20c romm it warms up to 18-19c. In effect you are working against yourself since the radiator is adding more heat to the water than your CPU block. Now the chiller actually has to work harder to keep it cooled to 15c.

So yes one or the other not both in the loop.

ElimGarak said:

Thanks for your input.

Please help me understand- I was gonna use the rads to lower the coolant temps (esp. if I overclock) so that the chiller didn't have to work so hard. Is that still a viable thing to do, or should I just go either the chiller route, or rads and pumps? And since I was gonna lock the coolant temps to -5 from ambient, I'm not too worried about condensation, but it's always good to be prepared...

Again, thanks for educating me...

Click to expand...

Cooling the water by using rads before it hits the chiller can only work if you use veeeeryyyy loooooooong hoses, very big rads and very slow pump.

Currently, a normal loop runs at 1-1.5GPM, this means that the water spends at BEST one second in the block/rad/chiller.

Your thinking comes from the assumption that there are massive energy dumps taking place during the cycle. But there are not...
Do you know why an A/C can not cool down a room if you leave doors & windows open? Because every time the air in the room passes through the A/C, a few degrees get chipped off... an A/C does not take 250 Cubic Feet of air and cools it off "in one go" from 35°C to 25°... the energy requirements for that would be ginormous.
The A/C chips away at the total volume of air one degree at the time, everyt time the air passes through the A/C

Any cooling or heating solution works (more or less) with the same principle.

A watercooling loop works on the same principle.. when the milliliter of water is in the CPU block, it "picks up" x watts of energy -say 2°C , when it goes through the rad, it "dumps" those x watts to the air... rince-repeat times the number of milliliters total in your loop and at some point there is an equilibrium.. if you have lots of radspace, then the loop temp is between ambient & ambient +10°C. If you have little radspace, the loop temp is (much) higher.


Now, about adding rads before the chiller in the loop... as long as you are using the chiller to keep the loop at ambient or just above ambient, yes they help.

However, if the goal is ambient or just above ambient (eg Ambient + 10°c)... then lotsa radspace will be cheaper as the $1400,- Koolance

If the goal is ambient or just below ambient (eg ambient -5°c), then the rads will just be an additional load for the chiller, iow they will be fighting the chiller.

Now, all this is of course "in general", you have to run numbers to know for sure...
.

Now, waterchillers & aquarium chillers are not really build to replace a radiator... They work best with a huge volume of water and a secondairy loop.


PS: of course, if you use (electronic) bypass valves, then you can have both ... water loop goes through rads (not the chiller) when idle; and when you want extra cooling, you flip the valves so the rads are cut out of the loop and the water goes through the chiller.
A bit like a small central heating setup

OK, I get it....Seems like my idea wasn't so great, and that's all right- that is part of learning.

Since I want a smaller sort of setup, would a 140.2 and 140.1 or a 120.3 and 120.1 be right for my components, or would the chiller be enough?

Any thoughts on the PSU? And what is the prevailing wisdom about putting rads above the level of reservoirs?

The chiller would work, but in my opinion is horrendously expensive for what you get. 140.3 or 120.4 is plenty of radiator for a quad core and single video card, I run a quad core and dual video cards on 120.4 with push/pull 1450rpm fans.

Radiator above res is fine with strong pumps, but air pockets can form so you may have to tilt the case to work them out.

Any thoughts on how to change the mounting threads on the rads I want (80mm Monsta's) and the chassis from m3 to m4? I read some things that made me want to have better reinforcement, since this PC will be moved occasionally for LAN partys and such. I can prolly do an easy DIY if someone can clue me in...

Since I got no response about the Corsair 860i, I decided to go with an EVGA PSU.

Drill'em and tap'em
http://www.frozencpu.com/products/1...ap_3_Piece_Set_-_M4_x_07.html?tl=g12c133s1365

I don't advise a custom liquid cooled PC to be mobile but if you must, well just grab a external housing with a MORA3 rad with a built-in reservoir/pump and have it connected to the PC via QDCs. All I would cool is the CPU and GPU.

Since you're learning and new to this, please take the time to read the water cooling yellow stickies. Only way you'll better understand what is at hand here etc.

GTXJackBauer said:

I don't advise a custom liquid cooled PC to be mobile but if you must, well just grab a external housing with a MORA3 rad with a built-in reservoir/pump and have it connected to the PC via QDCs. All I would cool is the CPU and GPU.

Since you're learning and new to this, please take the time to read the water cooling yellow stickies. Only way you'll better understand what is at hand here etc.

Click to expand...

^^^this