BeQuiet 240mm AIO overheating

Angry_Kittens · 15 Apr 2017 at 22:01

Recently replaced the water cooling loop on the Build from Scan (going 2 years strong) as I upgraded the graphics card to an Air Cooled 1080ti, I decided to do away with the custom loop and go with an AIO for the CPU - the BeQuiet 240mm AIO loop.

CPU is a 4790k @4.6Ghz

Since installing the BeQuiet loop, on running Prime95 Blend test, it jumps from 30c idle to 65c, then within 7 minutes it is topping out at 100c, the fans are going full blast to no avail. If I run the main heat producing Prime test it jumps straight to 90, then hits 100c within a minute. Although doesn't appear to throttle itself or crash. Temps measured in RealTemp

Seems to hold at 60-70 in game, which is it's main use.

I have already re-seated it twice but no joy (using the paste provided), still doing the same thing, the pump is definitely working, although connected to a 12V rail from the PSU, not on a Mobo header.

Any ideas?

orbitalwalsh · 17 Apr 2017 at 10:51

Try Intel Xtreme Utility or ASUS Realbench when stressing your CPU , Prime my just be flaming your CPU when its not really needed.
Would also switch to running the pump off your mobo and not your PSU! least with mobo you can set speed you want and warnings if pump fails! Connection to PSU could fail and you'd never no about it till a hard crash or worse.

also not system isn't filled the best so worth topping up, and if you hear bubbles in the CPU unit turn it 180 degrees and mount.

havent run Prime since changing from i7 860/ Quad core

gbgt2 · 18 Apr 2017 at 10:22

Stick with version 26.6 if you are using Prime95. The later versions of Prime after 26.6 run AVX workload and will produce really high and unrealistic temperatures with your CPU. With X99 (that I have) and I believe Kaby Lake as well you can set an AVX Offset in the BIOS to reduce the CPU core clock when AVX workload is detected to mitigate this.

Chaoss · 19 Apr 2017 at 00:51

I've fixed a few computers with "bad" AIO coolers, and in every instance it was not the cooler but was instead the way the pump was connected.

First you need to make sure that the 'pump' power connector is connected to a fan header that is marked as 'PUMP' and is designed to have a pump connected, otherwise the pump will be supplied insufficient power and will overheat. If your motherboard does not have a pump compatible fan header you can use a MOLEX (or SATA Power) to fan header adapter cable. I'm surprised more AIO instructions don't warn about this. Also connecting the pump to a 'normal' fan header can in some cases damage the motherboard.

If the above doesn't help or you're already connected to a fan header, check in the bios for fan speed options and set the 'fan' speed to max for the header that the pump is connected to.

Lastly if that doesn't work, make sure the fans on the radiator are oriented correctly (pushing or pulling air OUT of the case, not into it) and that they are working. Those temps are definitely way too high.