My i7 8700k is getting unstable when I try to speed it up, and things are going wrong lately.
My i7 8700k is getting unstable when I try to speed it up, and things are going wrong lately.
My cooler is an Arctic Cooler i30 CO, and it's been working great for a long time. The box says it can handle up to 160 watts of power. But the specs say I should be okay if my CPU uses as much as 160 watts of thermal design power (TDP). Here is what I see: The cooling performance max out at 320 watts, but Prime95 on stock settings keeps pushing more than 82 degrees Celsius while the voltage stays around 1.123 volts.
It's been working fine because your Intel Core i7-8700K usually isn't pushed to its limit unless you run stress tests. I'm not sure where the extra cooling power comes from for that model—it must be coming from the whole system, since the other coolers with 320w TDP are much bigger than this one alone. Also, if that i30 cooler really had 320w of TDP and wasn't just 160w, you wouldn't be getting thermal throttling in Prime 95 right now.
I know that running prime95 is really hurting my computer, but the problem started in handbrake when I used an overclock for a couple of years. First, my machine froze while using handbrake with the 4.8Ghz setting and -30 offset. When I changed the offset to -20, handbrake worked fine. But my heat levels are higher than usual everywhere, not just in prime95. Even when I'm sitting still, my temps hit between 35 and 40 at 4.8Ghz. Also, I don't usually stress test my system often. Just occasionally doing video encoding or something like that.
I notice a small shift, but it doesn't tell me if the voltage core is actually rising or falling.
I am sorry, so my voltage is about 1.23 volts for a 4.8Ghz chip that has an offset of -20, the package draws about 160 watts, and the temperatures are around 92 degrees.
That... is low, at least according to Silicon Lottery's binning statistics for that cpu: Coffee Lake All Core SSE Frequency All Core AVX2 Frequency BIOS Vcore % Capable 8700K 4.80GHz 4.60GHz 1.375V 100% Top 99% 8700K 5.00GHz 4.80GHz 1.400V Top 83% 8700K 5.20GHz 5.00GHz 1.425V Top 17% 8700K 5.30GHz 5.10GHz 1.437V Top 4%
Yeah, my computer is still hot to the touch even when I'm just sitting there doing nothing. The temperature seems to be around 35 or maybe 42 degrees Celsius, which used to be fine before. It sounds like either the fan isn't working right or the thermal paste on it isn't sticking well enough to handle the heat.
ian.egerton , There are several variables and possibilities to consider with respect to Core temperatures and stability. Although Throttle temperature is 100°C, Core temperatures above 85°C are not recommended. Core temperatures below 80°C are ideal. The Arctic Cooler i30 CO is barely adequate for the i7-8700K at stock, but not when overclocked or when Package Power is as high as 160 Watts. Although transcoding software such as HandBrake runs AVX code, the peak fluctuating workload and power consumption typically shouldn't exceed the steady-state true 100% workload of Prime95 Small FFTs with all AVX test selections disabled. If Core voltage at 100% workload is only 1.23 then processor degradation is extremely unlikely , which typically doesn't begin to occur on 14nm processors until Vcore exceeds 1.4 as Phaaze88 has pointed out. However, motherboard VRM degradation is always possible, which can cause unstable power delivery to the CPU power plane resulting in intermittent instabilities and BSODs, especially when lowest Vcore sags occur during highest peak workloads, as keith12 has pointed out with respect to LLC. You may be experiencing memory instability, which is often difficult to isolate from CPU instability. Record the error message(s) and code(s) when BSODs occur. Use a pink eraser to clean each module's edge connector contacts, then reseat and / or swap modules to different slots. You can increase memory voltage in 10 millivolt (0.010) increments to see if your rig stabilizes. It would also be prudent to run MemTest86 as well as Windows Memory Diagnostic Tool. TIM (paste) degradation is most obvious at 100% workload due to high power and thermal dissipation, but is much less noticeable at idle due to low power and thermal dissipation. This also applies to Intel's internal paste between the Die and the Integrated Heat Spreader (IHS), which also degrades over time. In such scenarios, the only solution is delidding. Complaints about high idle temperatures on various websites and forums are commonly made by users who are highly inconsistent about what the term "idle" actually means. Idle means just 1 or 2% CPU Utilization in Windows Task Manager; not running a light workload and surfing with various browser tabs open while streaming, etc. Unnecessary background Processes and Services account for spikes, fluctuations and high idle temperatures, especially when combined with high ambient temperature. Most users don't mention ambient temperature which can be a huge variable. Many aren't accustomed to monitoring thermal behavior, so Core temperatures may go unobserved for countless months. Seasonal indoor ambient temperatures might be 10°C near the Arctic Circle, or 40°C without A/C near the Equator, which affects all computer temperatures, whether at idle or under 100% workload. The International Standard for "normal" room temperature is 22°C or 72°F. So when providing full system specs, it always helps to include ambient temperature so we know whether or not your rig is running in a reasonably normal environment. CT
Hi, thanks so much for responding! My room gets up to 22 degrees during summer months. Since everyone else is having trouble with heat, I might check out a better cooling option like the Noctua NH-D15. If that helps, everything will be fine. I already ran memtest and all passed, too.
Update. So I took out the heat sync and cleaned everything clean, then put new thermal paste back on. There is a big improvement of about ten degrees for both when not using it and when working hard. I can keep my handbrake running at 4.8Ghz with a VCore of 1.23v staying steady while the temperature floats between 72 and 74 degrees. My idle temps are now down to 32-34 degrees. The handbrake only pulls up to 160W when I'm running, so my Arctic Freezer can handle that. Even when running Prime95, it still fails because the power drain goes higher than 200W+. I think I will go ahead and buy the Noctua NH-D15 (I just need to measure to make sure it fits in my Corsair Carbide 300r, which I believe it does).