CPU to GPU?

[Fudd Rucker]

Im planning on overhauling my watercooling system and was wondering if it would be a bad idea to run directly from the cpu to the gpu then out to the radiators? Or would the water be too hot from the cpu therefore negating the purpose of watercooling the gpu?

Im planning on using 4 x yate loon + 2 x sflex 1600rpm fans with a TFC Xchanger 240 and an MCR220 in a giant pushpull fan sandwich. The CPU block is an EK supreme LT and the VGA block will be an EK 5870 full coverage block. The line is running 1/2" tubing and using an MCP655. I would like to cram the whole unit into a custom box later on with everything inside the external custom box and just lines running in and out.

[Jackquelegs]

Water doesn't transfer 100% of the heat from the CPU block to itself. The water out of a CPU block does not have the same temperature as the CPU block. Likely it's going to be around 5C above the ambient temperature if your flow is good. Hence, it's not a huge impact by having CPU - GPU.

So with CPU-GPU you'll see a slightly higher temp on the GPU, however it's almost negligible since the temps on a card is going to be excellent with water anyways.

[Zero82z]

The order of the loop really doesn't make a difference, so you'll be fine if you do that.

[chrisk]

I was wondering the same thing a while back. From what I was able to find, after a few minutes the temp of the whole loop evens out as the water is circulated.

[Fudd Rucker]

Thats good to know, Im fairly confident the 2 radiators should net me excellent temps for both CPU and GPU. The gpu cooling is maily out of necessity than performance as the referance 5870s are ridcilously loud and noisy. But I have gotten this sucker to run @ 4.4ghz though, but couldnt keep temps within range so thats my goal.I would also like to see 1000mhz core/1500mhz mem speeds on the video card as well while having it run dead silent.

[biff]

A clean layout is more important than order. The temp difference as the coolant passes through the CPU block should be very minimal, much less than anything that would make a difference to a GPU.

[like 30 ninjas]

keep in mind your GPU won't lose performance as much if the temps are high, compared to a CPU

[gingerbee]

it's all about ambient and your rad.

[Zero82z]

Originally Posted by like 30 ninjas

keep in mind your GPU won't lose performance as much if the temps are high, compared to a CPU

Temperatures don't affect performance at all, regardless of whether you're dealing with a CPU or GPU.

[Dazmode]

Originally Posted by biff

A clean layout is more important than order. The temp difference as the coolant passes through the CPU block should be very minimal, much less than anything that would make a difference to a GPU.

I'm with Biff. +1

I have single loop myself: ...CPU - chipset - GPU1 -GPU2 -.... Works great.