Running Hot


Hello all,

I have been building computers for a long time and with my most recent build I have run into an issue I cannot solve.

I have a Lian Li Lancool 205 case, an MSI MAG Core Liquid 240 with 2 Lian Li Uni Fan SL120 fans attached. It is cooling an AMD 5800X3D. I have an MSI B550 Tomahawk Max Wi-Fi motherboard and an Nvidia 3090 Founders Edition.

The radiator is mounted at the top of the case and the fans are mounted as intakes on the bottom of the radiator. There is a mesh filter on the top of the case. There are two 140 MM fans at the front of the case as intakes and one 120 MM fan at the back of the case as an exhaust. The front fans are the included Lian Li fans and the rear fan is another SL120, same as the radiator fans.

The CPU is running abnormally hot. Idle temperatures are 45-50 C and during gaming it's getting up to 85 C. Running a prime 95 stress test will see temps hit 95 C immediately and the CPU will thermal throttle. I ended the test right away as I was afraid I would damage the CPU if it continued running. I will see lower frame rates in multiplayer games than with my 5600X that was on air cooling. My room is not very hot and is usually around 70 F most of the time.

I have tried the following to fix the problem:

Removed pump/heat sink and checked the thermal paste. The paste had fairly even coverage and was not dry. I re-pasted with the same Corsair TM30 as before and made sure the pump/heatsink was tightened all the way down. I removed the fans and checked the radiator for dust and hair, it looked clean but I used my data vac anyway and blew it out. I checked the top and front filter for dust and hair and gave them a cleaning, both were still fairly clean. No change in temperatures.

I reset the BIOS to factory settings. The only things I had changed were turning on XMP for my RAM and turned on resizable BAR. I tried to make sure any automatic overclocking features were turned off. This is my first MSI motherboard so I am unsure if I did this step correctly.

I set the pump speed and all of the fans to maximum speed.

This lowered the temps of the other components in the system but made no difference in the CPU temps.

The motherboard and CPU socket are around 32 C, the GPU idles at 37 C and stays at 60-70 C during gaming. Nothing in the system is overclocked.

I am stumped at this point. Does anyone have any ideas or suggestions I should try?



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