Large difference in idle and load temps?

RollerBall · 21 Nov 2017 at 15:40

Setup:
EKWB 250x3 res -> D5 pump /w EKWB top -> XSPC 480 radiator -> GTX 1080 /w EKWB -> 7600k /w EKWB supreme HF. Mayhems pastel yellow coolant.

Idle temps around 25-28*C for both the GPU and CPU.
Load GPU can get up to 80*C after a few hours of destiny 2, CPU getting up to around 60.
Everything running on stock.

Although the WC hardware is a bit old, I can't imagine it failing to keep up this much. I'd be inclined to think the seat of the blocks if fine given that the idle temps are only a few degrees above ambient.

At the moment, I'm thinking it may be that the fans are old/not working very well. Two are 120mm silverstones that came with my TJ07, the other two are Yate Loon D12sm, all four at 7v via 3 pin to molex. Occasionally I notice that one of the silverstones isn't running until I give it a little flick to start up.

I'm thinking of changing it to phantek PH F120SP as they can be had from a competitor for around a fiver and I find it difficult to justify ~£80-£100 on four fans.

Thoughts?

Legend · 21 Nov 2017 at 18:38

For WC those load temps are high, particularly for GPU. On air you'd be looking between 80-90 under load really.

I would not imagine fans will make that much difference, assuming they are spinning. They'd have to be awfully rubbish to make more than a few degrees difference, so I don't see that being the culprit.

Did you ever have temps running much lower than this, or has it always been this way?

By all means try new fans if you want, assuming that's a quick swap, but I doubt that will help. I would be inclined to suggest you do a full drain and tear down, re-seat blocks and apply new TIM... although I know that's a lot of work.

Radox-0 · 21 Nov 2017 at 21:18

I doubt its your fan's. Those temps lead me to believe its a flow issue or the block is simply not mounted properly. Do you have any temps that measure flow rate or water temp?

Reason why I likely think its block / flow rate, is GPU blocks usually do a good job of transferring heat into the loop and usually under load the CPU will be warmer. At 80 degrees on the GPU, if the flow / block contact was fine, the water would also be very hot and things like radiators / blocks would be noticeably warm to touch. I would agree with Legend, strip the blocks down, re seat and ensure your pump is working fine.

RollerBall · 21 Nov 2017 at 22:17

I can a tear down and re-seat if needs be (tonight CPU got to 68, GPU to 77 after playing destiny 2 for 4-5 hours), but I want to explore the 'easier' options first.

I'm going to check my pump isn't undervolted without me knowing tomorrow, but it's more effort to re-do the entire loop (I've not long re-done it 2-3 times to flush etc for a new build) and I wouldn't have thought I'd messed up the seating on both CPU and GPU.

Legend · 22 Nov 2017 at 13:44

Fans never make that much difference in my experience, and even not when you look at group tests done by the pros, so I'd be amazed if that was the issue. By all means try that if it's easier, but I doubt that will solve anything.

Regards the pump, I don't think you'd be seeing THAT much of a difference if it was undervolted... it would practically have to be not working for it to make a double digit degree difference. As I say, did you ALWAYS have temps like this, right from when you first put the build together, or was it running cooler before?

Perhaps if you post pics it might help.

BluD · 22 Nov 2017 at 14:22

Gpu seems way too hot, i would definitely remount that. Low IDLE and high LOAD temps are normally a poorly mounted cooler in my experience, if it was down to fans or trapped air then your temps would also be staying high for a while when you go back to idle from load.

RollerBall · 22 Nov 2017 at 15:42

It's a new build so I can't comment on previous temperatures - I've used the CPU block/rad/pump in previous builds and the temperatures have been fine. Following another period of gaming today the temps got up to 64 and 68 on the CPU/GPU. After about half an hour they've returned to low 30s.

Tbh, I don't think flow is much of an issue. When I was running it with distilled water prior to pastel yellow the res wasn't filled up as much as I could see a decent output from the top. I'm going to have to order some more fluid anyway if I'm going to remount everything so I may as well replace the old fans at the same time. I have lots of pics of the re-build, including how much paste was on the CPU but not of the GPU pre-mount. I can find somewhere to host them, but I'm not sure it would add a whole lot.