Do you have a new i7-6700k? I am wondering what you should do to run it at 4.5GHz.
Do you have a new i7-6700k? I am wondering what you should do to run it at 4.5GHz.
I've got an old system running on mostly 5-year-old hardware and finally getting around to overclocking it. I'm trying to squeeze a little more life out of the gear so I don't have to buy new stuff right away. But I am having trouble with stability and heat, especially since what I read about this processor doesn't look normal. So I hope you can help me get a few more megahertz while keeping my CPU cool and steady here are my specs: an i7-6700k running at 4.00GHz (base) on an Asus Z170-A mobo with 2x8GB of Crucial Ballistix Sport memory at 2666 MHz CL16, no Noctua NH-U12A cooler yet, a Phanteks P400A-Digital case, and a GIGABYTE RTX 2070 Gaming OC card with 8G. The case and cooler are new because my old ones were messed up and too loud. I bought the RTX card after I fried my old 980Ti in late 2018. My first attempts at overclocking worked well enough to get my system running at 4.4GHz just by adjusting the multiplier without touching anything else. I ran Prime95 for hours and it worked great, and my core temperatures never went over 75C. I then tried going to 4.5GHz and had similar results where temps got high but seemed fine. Then I tried 4.7GHz which was okay enough to push to 4.8GHz. But that one made me pause because my Core 0 temperature started hitting 95C, which I knew was too much. So I went back to 4.7GHz. To figure out how best to drop the temps so I could try again at 4.8GHz, I read up on how to properly overclock an i7-6700K and realized something: I had accidentally left my mobo's automatic VCore setting turned on. That's why those temperatures sometimes hit 95C; it was likely because the mobo was pushing the voltage way too high in its attempt to stay stable. So I started doing things "properly" based on a guide from TweakTown, especially that flowchart. Unfortunately, even at the first recommended OC (4.5GHz at 1.3v Vcore), I got severe stability issues right away. Prime95 threw a hardware error very soon after starting it, and IntelBurnTest froze up. After trying new stress tests over the weekend and messing around for hours, I was disappointed to finally settle on an OC at 4.5GHz running at 1.34v Vcore. That passed about 20 minutes of Prime95 (with AVX disabled) and 15 minutes of RealBench stress testing (which I read as a better way to test for AVX stressing). It didn't crack Core 0, which is often 3 to 4 degrees hotter than the other three cores. Higher multipliers made the system unstable, and higher voltages made the CPU too hot (>85C after a few minutes of load). Did I just badly lose the lottery on that chip? Is it because my CPU is 5 years old? Or is there something I can do to improve this situation? Maybe try applying thermal paste better? I have some Kryonaut paste from Thermal Grizzly, which I got just in case I needed it. But my Noctua cooler came with NT-H1 thermal paste already, so I used that. Any help would be greatly appreciated!
What temperatures do you feel if you turn it on while using power? Does your motherboard BIOS need updating to version 3802? If not, restart it and refresh the BIOS settings before trying it all over again. Follow these steps carefully.
So I put a new CPU cooler back on my PC and found something interesting. I think I used not enough thermal paste because there wasn't really any in the middle of the CPU when I took the cooler off. It was mostly clear, and you could read most of the text easily. This probably means I tightened the cooler down too much, which pushed all that heat pasting right to the edges of the CPU. So this time I added a bit more thermal paste (it's a pain because they don't have a sharp nozzle for Noctua coolers; it's just a flat hole at the end) and screwed the cooler down not as hard. The results so far look good. During Prime95 Small FFTs, my average load temps dropped from 70s to 60s, and max was 77 instead of 79 with RealBench also reaching high 60s averages while hitting a max of 77. I'm currently testing a 4.5GHz overclocked CPU and running RealBench right now. After fifteen minutes, it's averaging in the high 60s for load temps. There was just one short spike to 80 on Core 0, which is still by far the hottest core under load (interestingly, Core 1 is clearly the hottest when idle). To my surprise though, this 4.5GHz CPU stays stable with a stock vCore of 1.300v. In my last tries at 4.5 before I followed all the advice in the guide I linked in my previous comment, I couldn't even boot with a 45 multiplier at 1.300v. I had to boost it all the way to 1.340 to stay stable during stress tests. But now (apparently) I'm stable at 1.300v, which is awesome!
Well, I decided not to try 4.6GHz anymore because it gets too hot and is unstable at lower voltages below 1.36. So now I'm testing 8 hours on 4.5GHz at 1.310v to see if that works out. It seems like maybe the chip was just outdated, or my CPU isn't good enough for high-end overclocks. In any case, I did my best and followed every step correctly. Now I have a 12.5% boost with low temperatures so my fans stay quiet—that's sweet. Plus, I learned a lot for next time!
Honestly getting 4.4 volts on stock voltage feels pretty good, so you didn't miss out on the chip lottery. It might actually be more stable if you run it at lower voltages.
I wasn't really getting stock voltage; I was using "Auto," which made my motherboard bump the voltage up automatically to keep things stable at higher clock speeds. Anyway, since you brought this thread back up, here is a little more story from my overclocking journey. I took out the CPU using the razor method and it went very smooth. I saw a drop of 10 to 12 degrees Celsius, which got me excited to try going 4.6 GHz again. I tuned down to 1.4 volts, and at first it looked promising. It survived an overnight RealBench and an overnight Prime95 blend with max core temps under 85 degrees C, and the averages came out in the middle 70s. But when I started playing games, things got worse. After three crashes (Blue Screen of Death) during one long day on the game Prey, I had to give up on 4.6 GHz again and drop back down to 1.34 volts at 4.5 GHz. It's been working great for another full day now, so I'm just going to keep this until I buy a new CPU. The fact that I apparently need more than just .06 volts extra to stay stable when clocking up by 100 MHz on a chip that people regularly overclock by 200 MHz beyond the highest I can get with a delid tells me I lost my chance at winning on this one. 🤷
Haha I made a mistake because the thread was already so old. Yeah that 6700k is super picky. Mine runs at 4.5GHz at 1.268v which is really cool, but i also can't run it higher than 4.6 without needing almost 1.4v. That old chip lottery was a big deal, good luck to you with your delidding!
I am going with exactly what I saw, because getting a solid 5.0 was hard and I wasn't even close to keeping it steady. The i7 6700k is actually really bad when you try to Overclock it (OC). I remember having an i7 4790K running at 5ghz without any problems back then with great cooling. Man, how young I was back then and didn't understand computers until later, and honestly now I have no idea why that one worked so well lmao. But yeah, I wouldn't push the i7 6700k too far because it gets unstable after hitting 4.8ghz. It's not worth stressing out just to run at 90 degrees for a few hours under full load without going down.