Know how to properly verify a stable CPU.
Know how to properly verify a stable CPU.
Prime95 performance appears excessive; verify temperatures during Cinebench runs.
Which version of Prime95 are you running? If it's 26.6 or lower, 99c is definitely too intense. I’d even suggest it’s too hot for AVX versions. Occasionally, some of my CPUs handled more than a few seconds of AVX2 Prime before stalling, and temperatures never exceeded around 80°C. Regardless, 99 is quite warm.
I think Prime95 is quite excessive, my PCs stay well-cooled and never face overheating problems even during normal use (like playing AAA games). But after roughly five minutes of running it, the CPU temperatures reach around 90°C. If your machine can handle Prime95 for an hour without issues and stays cool, you're in a good position.
I understand the situation. While I can handle modest FFTs throughout the day on versions 26.6 or earlier with temperatures under 60°C, performance drops significantly after that. After a few days of monitoring clocks and voltages while playing games, I’ve noticed much smoother operation thanks to AVX2, avoiding crashes or BSODs.
I resolved the issue by running 26.6 or lower, or updating to the latest version and turning off AVX in the settings file. Now normal temperatures occur during load while still conducting intense stress tests on the CPU, which was my goal. I performed several benchmarks that all executed smoothly with good outcomes, but my system remained unstable under the workload. I needed a more rigorous stress test to improve performance and stability over extended periods. The temperatures I observed are comparable to other benchmarks, yet the CPU handled testing better and resulted in fewer crashes—something I found positive.