What am I doing wrong?

[GoogalyMoogaly]

I've recently re-done my watercooling for the 3rd time.
I've gone from:
CM 690 II
240mm XSPC RS rad
240mm EK rad
Gigabyte GA-880GM-UD2H
Phenom II X6 1055T @ 3.5GHz with HeatKiller 3.0 Cu CPU block
4870x2 with EK 4870x2 block
Swiftech MCP35X fitted into a XSPC dual-bay res
Feser Bi-distilled water
4 x Akasa Vipers (usually running at ~1300rpm)

To a:
CM HAF 932
360mm Black Ice SR-1 rad
120mm EK rad
Asus M5A99X EVO
Phenom II X6 1055T @ 3.5GHz with HeatKiller 3.0 Cu CPU block
GTX 480 with XSPC 480 Razo full-cover block
Swiftech MCP35X fitted into a XSPC dual-bay res
Mayhem Red Pre-mix fluid
4 x Gentle Typhoon AP-15 (running at around 900-1000rpm)

My temps previously weren't fantastic but weren't bad (CPU low 40s under load, GPUs ~50ºC while gaming or running Heaven), it was just a bit noisy running Vipers at ~1300rpm and probably a bit higher when under load.

Now my temps are worse! My CPU was hitting 48ºC after 90mins of Prime 95 SFF and the GPU hit 55ºC after 1 run of Heaven.

Why did my temps get worse?
The air coming out of the rads is cool and the dual-bay res is cool to the touch, previously the water in the bay res would get warm as would the air coming off the rads.

The GPU block looked to have good contact after I fitted it (I might have put a smidge too much TIM on it) and the CPU block doesn't seem like something you can really mount wrong, unless I used too much/little TIM, but it was about a pea sized amount.

I used ICDiamond24 on the CPU and Arctic Ceramique on the GPU (didn't have any ICDiamond at the time and didn't want to use AS5 as I wanted something non-conductive).

Anyone got any ideas as to what's not right?

Thanks in advance for any help.

 

[GoogalyMoogaly]

I didn't think the GPU temps were too bad as I know 480's run hot, but then so do 4870x2s.
The CPU was my biggest concern. With TIM is it better too have too much rather than too little (obviously it's better to have it exactly right)?

The sequence of my loop is:
res/pump -> CPU -> GPU -> 360 rad -> 120 mm rad - res/pump

 

[GoogalyMoogaly]

Sorry, meant to post this pic in the initial post:

Shows my layout.
Now that you mention it, in my old loop I did have it:
Res/pump -> XSPC rad -> CPU -> GPU -> EK rad -> res/pump.

I thought that temperature 'transfer' worked best at extremes, so thought if I put the rads after the block they'd work better as the water would be hotter. I know people say that temp even out across the loop so order doesn't matter, but it just doesn't seem logical to my brain so while I try to keep that in mind their a little voice it the back of my mind saying it does!

 

[GoogalyMoogaly]

I would try

Res > CPU > rad 120 > gpu > rad 360 > res

I did think of that originally, but it just wouldn't be practical from a tubing point of view. you'd have 3 bits of tubing going infront of the fan for the 120mm rad and I think it would just be awkward.

I think your problem is just as a result of using lower speed fans to be honest. the 480 is roughly comparable to the 4870X2 in terms of power consumption so heat dump into the water isn't that much different.

As long as you've got the res before the pump it won't make any real difference what order you have the blocks.

I was slightly afraid it might be partly to do with the fan/pump speed as I was hoping that with the SR-1 rad I could run fans slower and thus quieter. Also, I'd have expected the res to feel warmer if the rads weren't removing the heat from the water.

The thing is when the CPU was running Prime and getting hot the GPU temp seemed to increase a bit too, so unless it was just coincidence it would seem the heat is being transferred, it just doesn't seem to be noticeable in the res or from the air coming off the rads.

I have started to wonder if it may be a few smaller things combined. For a start the fans and pump running slower (pump is PWM and the new Asus board allows better control than the Gigabyte did), also mlwood37 stated that the Pre-Mix has been tested to be only 2ºC above water (but still that 2ºC possibly accounted for, guessing 2 is an average so maybe more/less in my case) and someone mentioned about the pump dumping some heat into the water and previously I had a rad before the components. but that last point doesn't work if the order doesn't matter and the temp averages out. But in that case, maybe the 480 is dumping a little more heat into the loop than the 4870x2.

Maybe if each of these things only added 1-3ºC each then that's 3-9ºC in total. My temps are only around 5-6ºC worse (from testing done so far) so that could account for it. Also maybe I didn't apply the TIM as well this time.

I might stick with it for the minute, maybe turn the fans up a bit (but half the reason for the rebuild was so it would be quieter). Then in a little while (maybe when it's due anyway) I'll switch the Pre-Mix out for plain distilled water. I might also re-mount the CPU block (which is easier when you can lay the PC on it's side (tricky with a bay-res full of water)) and see about arranging the rads before the CPU and GPU I know it shouldn't make a difference, but just a few degrees might swing it.

the idle temps weren't actually too bad. I think the CPU would idle in the low 30s and the GPU in the high 30s. I'd have expected worse if there was too much of an issue with block mounting.

Thanks for all the thoughts/suggestions/advice so far.

 

[GoogalyMoogaly]

I'm not familiar with the heatkiller internals, but it won't make any difference unless the pin/block design is very particular.


edit:
out of interest, what is the foam beneath the gpu gpublock, is it arond your drain tube? Nothing to do with your temp issue, just curious.

Heh, that's not foam, it's a piece of wood I put there to help support the VGA card. It's just taking a little bit of the weight. I'm hoping to replace it in the future with something a little more permanent and better looking

 

[GoogalyMoogaly]

The middle one is the input (or at least the one I'm using as the input). Wasn't easy to figure out from the instructions. I actually had to get Google to translate the German instructions because the English ones were so vague.

 

[GoogalyMoogaly]

Oh yeah, definitely quieter.
All fans are pushing.