a200 CPU Coolant not heating up

[CerebralTag]

Just got the CorsairOne Pro a200 late last week and have been having issues with it. In troubleshooting I noticed that the the CPU coolant is usually ~25-30C below the temp of the CPU package body. This is sustained over hours. The CPU idles ~50C and easily gets to 80-85C under load. I understand that the chip is designed to run hot and the unit will keep the fan to a minimum, and I'm no expert on water cooling. Over time shouldn't the coolant heat up to a level closer to the CPU temp? That seems to be the behavior of the GPU and coolant.

 

For reference after three hours with a browser running the CPU is ~60C and the coolant is ~40C. The coolant was 34C ten minutes after boot.

 

Is this expected?

[Queeg]

That’s similar to my experience with my i160. I know the CPU in my machine runs cooler than yours, but my coolant temperature is usually in the mid 40s even when the CPU package temperature is in the 70s. So long as your CPU temps are reasonable, I wouldn’t worry about the coolant temp. Seems to me it’s working well for you.

[Azureblood2]

That is normal, The CPU will always be hotter than the coolant temp. The coolant is constantly transferring heat to the radiator which is being cooled by the fan. Normal coolant temps will be between 30 and 60c, and normal CPU temps will be between 45-80c.

 

Thermal conductivity plays a big part in how much heat can actually be transferred to the coolant. When you put more load on the CPU it will generate more heat, and the coolant temps will rise. Once the load is removed the CPU will quickly cool down and the coolant will gradually cool down.

[CerebralTag]

Thank you both so much for the feedback. The CPU cooler block wasn't tightened very well, I have hand tightened it and that lowered my idle temps ~5-8C . It also seems to be allowing the coolant to heat up quicker as the chip heats up. Still the behavior Azureblood2 described, but much better than it was.

[Azureblood2]

When I re-pasted the CPU block on mine... Corsair DEFINITELY skimped on the thermal paste... it was actually really bad... I could easily make out most of the print on the CPU.

 

It probably wouldn't hurt to grab some good quality thermal paste and redo it. I personally use Thermal Grizzly Hydronaught.

 

Also, you can bottom out those screws they will stop well before they put too much pressure on the CPU. Just Do it evenly on both sides

[CerebralTag]

Awesome, thanks Azureblood2. I picked up some Kryonaut but was leaning toward leaving it alone since tightening it down seemed to help. At this point I'm not sure if this thing is going back or not. Even after getting the heat under control the whole thing seems unstable. BSOD for exception access violations and page faults in non-paged areas. Games crashing with what seems like GPU memory errors (also exception access violations).

 

I've tested with memtest86, Windows Memory Diagnostics, Prime95, BurnIn, and 3dMark all without issues, but somehow actually using the thing is an exercise in constantly losing work. Would you happen to have other ideas of what to check?

 

Much appreciated!