Can you get a good temperature for the i7 8700k when overclocking at 5GHz?
Can you get a good temperature for the i7 8700k when overclocking at 5GHz?
Hi, I recently set up a new rig and attempted overclocking for the first time. I increased my new I7 8700k to 5GHz. During full load on Prime95 it reached 79 degrees for a brief moment, then settled around 77 degrees most of the time. It never exceeded 79 degrees. Is this temperature typical?
It varies based on your configuration and the version of Prime95 you applied. For p95 versions 26.6 or earlier, it doesn’t rely on AVX instructions, resulting in a perfect 100% load on smaller FFTs. At 77°C this is ideal. Once you reach p95, AVX becomes active, which begins to affect performance. If you haven’t adjusted it yet, check the BIOS for an AVX offset of at least 2, around 200MHz. When AVX is enabled, the CPU will lower the clock speed accordingly—so at 2.0 GHz it would run at 4.8GHz at 1.3v. Using blend or large FFTs will also draw from both RAM and CPU, leading to much lower loads, meaning the 4.8GHz at 1.3v won’t be as effective.
It's actually quite interesting. Be careful not to anticipate such extreme heat during practical applications.
It varies based on your configuration and the version of Prime95 you applied. For p95 versions 26.6 or earlier, it doesn’t rely on AVX instructions, resulting in a perfect 100% load on smaller FFTs. At 77°C this is ideal. Once you reach p95, AVX becomes active, which begins to affect performance. If you haven’t adjusted it yet, check the BIOS for an AVX offset of at least 2, around 200MHz. When AVX is enabled, the CPU will lower the clock speed accordingly—so at 2.0 GHz it would run at 4.8GHz at 1.3v. Using blend or large FFTs will also consume both CPU and RAM, leading to much lower loads, meaning the 4.8GHz at 1.3v won’t be as effective.
It's a great overclock. It's very unlikely that any app requiring avx instructions will push your system to maximum capacity. Thus, temperatures won't rise excessively. Just keep it as it is. Once more, congratulations on achieving a solid CPU performance.
The AIO is performing excellently for you. My Noctua D15 supports 5GHz, though temperatures rise significantly while gaming—still manageable. I appreciate the CPU Package fluctuating between 55 and 75 during gameplay and 30 to 45 when idle. Just keep in mind to save your OC Profile from the BIOS onto a USB2.0 Flash Drive.