Running 9900k at 90 degrees Celsius on Prime95 with AIO
Running 9900k at 90 degrees Celsius on Prime95 with AIO
Hi everyone,
I just bought an i9 9900k and am attempting a 5 GHz overclock. So far, I haven't had any issues, but I'm concerned about the temperatures. During my Small FFT tests on prime95 v26.6, my CPU temperature jumped to 90 degrees instantly. Is this typical or should I be concerned?
The voltage during testing was between 1.315 and 1.325V and the power draw was around 190W.
Settings:
- CPU core ratio: 50 (all cores)
- CPU ring ratio: 47
- AVX Offset: Auto
- Vcore voltage mode / voltage: Adaptive = 1.330v
- LLC mode: 4
PC specs: MSI MEG ACE Z390, i9 9900k, G.Skill 16 GB DDR4-3200 (XMP enabled), Corsair CS750M
Best regards,
Jason
Hmm, that's on the low end of the scale. The ML240L is the 'lite' version, got the weakest pump, cheapest rad and fittings etc. Rgb means it supposed looks decent, but rgb fans do not perform as good as a plain fan, there's only so much room inside the motor housing and when a good chunk of it is taken up by the pcb and wiring the RGB needs, something has to give. Ever wonder exactly why Noctua has 0 plans to go rgb? It'd kill the brands look performance expectations.
So you'll pretty much expect temps that high, especially if you forgot to check the little boxs in the Prime95 setting to disable AVX, AVX 2 and/or AVX-512. The auto setting for AVX offset may not drop the OC frequency enough to satisfy your temp requirements, it's only...
Didn't mention what's causing the cooling issues. A 9900k at 5GHz locked core OC can easily reach between 200-250w. That's roughly the maximum of the biggest air coolers or a good 240mm AIO, particularly when motherboard makers play with Intel's suggested power limits. For heavy workloads like Prime95, a 360mm AIO or a full custom loop with over 400w capacity is advised.
Hmm, that's on the low end of the scale. The ML240L is the 'lite' version, got the weakest pump, cheapest rad and fittings etc. Rgb means it supposed looks decent, but rgb fans do not perform as good as a plain fan, there's only so much room inside the motor housing and when a good chunk of it is taken up by the pcb and wiring the RGB needs, something has to give. Ever wonder exactly why Noctua has 0 plans to go rgb? It'd kill the brands look performance expectations.
So you'll pretty much expect temps that high, especially if you forgot to check the little boxs in the Prime95 setting to disable AVX, AVX 2 and/or AVX-512. The auto setting for AVX offset may not drop the OC frequency enough to satisfy your temp requirements, it's only going to drop the frequency enough to maintain cpu temps under tjmax.
Additionally, I avoid using XMP and instead manually adjust the RAM speed. I also refrain from keeping VCCSA and VCCIO in AUTO mode, as this keeps the voltage at a high level, which further raises the CPU temperature.
Thanks for the update. I placed an order for a 360mm AIO for my processor. I was thinking about it before, but I still plan to purchase one.
Before you abandon your cooler...
My system performed well at 5.0GHz, but when I ran AIDA64 with FPU enabled or checked performance reports, it would either crash or slow down during ray-tracing. Neither outcome was ideal.
I reduced the overclock and at 4.7GHz it stabilized without throttling. I considered upgrading the cooler or using a more powerful one.
Then I looked at the H100i cooler settings—it was set to 'Quiet'. After changing it to 'Extreme' and rerunning the FPU test, the benchmark at 5.0GHz showed much improvement. Previously, it would exceed 200°F, cause throttling, and make mouse movement stutter; now it runs smoothly with maximum temperatures around 170°F.
Being next to it, I didn’t notice any difference until the temperatures rose and the fans started working harder.
The lesson is clear: ensure your cooler settings are optimal.