This problem began about two days ago. A game that previously ran normally started lagging badly on two consecutive nights, so I checked the system with hardware-monitoring software and saw unusually high temperatures on certain CPU cores, even while the computer was mostly idle. Other games still run normally, the GPU appears healthy, and RAM usage is normal. I opened the case and thoroughly removed the dust, but the temperatures stayed high. Occasionally, restarting produces a CPU over-temperature warning, requiring a full shutdown before powering the system back on. The system has a Ryzen 7 3700X, GeForce RTX 2070, and 32 GB of memory. I have not installed anything, changed settings, or moved the PC recently.
2 Answers
Some games can load the CPU much more heavily than others, so the full system specs and per-core readings matter. Since this is a Ryzen 7 3700X and only a couple of cores appear to be spiking, check whether a background process is keeping those cores busy. Also verify that the CPU cooler fan is spinning and that the cooler is firmly mounted; a bad contact or dried thermal paste can cause sudden high temperatures and boot-time over-temperature warnings.
Think back to anything that changed around the time this started, including game updates, unofficial mods, drivers, or newly installed software. Even if nothing obvious was changed, check Task Manager for a process using CPU in the background. If the temperatures remain high at idle and the BIOS also reports an over-temperature condition, the cooler, fan, pump if applicable, mounting pressure, or thermal paste should be inspected before continuing to run demanding games.
Nothing was installed or changed, and the computer has not been moved. That is why the sudden temperature increase is especially confusing.
The rest of the hardware is a GeForce RTX 2070 with 32 GB of memory. The strange part is that the high readings seem limited to two cores, even when the system is idle.