• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Overclocking 8700k - what would be considered good (not safe) vcores?

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.

MJBN77

New Member
Joined
Jan 2, 2018
Hi, I am currently in the process of overclocking my 8700k. My MB is MSI Gaming Pro Carbon and my CPU cooler is the beQuiet! Dark Rock Pro 3.

They goal is to find a super stable 24/7 overclock at 4.8Ghz and one at 5.0Ghz (maybe with an AVX offset of -2) that will not be used 24/7. I am using the following stress tests routine to test each voltage and clock setting:

1. 3 runs of Cinebench
2. 1hr RealBench stress test
3. 1hr prime95 v26.6 (small)
4. 3dmark extreme stress test

So far it seems I can run 4.8Ghz @ 1.24volts with LLC4 stable (stable according to the testing routine describe above). I worked my way down from 1.27volts. I still try to figure out the lowest stable voltage for 4.8Ghz.

Questions: what would be good (better than safe) voltages on an overclocked 8700k for a) 4.8Ghz b) 4.9Ghz and c) 5.0Ghz. I know a rule of thumb would be anything below 1.35V would be considered safe, but lets say below 1.25V would be even better.

Also, I notice when I overclock to 4.8Ghz with auto voltage setting, my board is using 1.24V as vcore under full load. Does that mean there should be room for lower vcore?

Thank you!
 

Johan45

Benching Team Leader Super Moderator
Joined
Dec 19, 2012
V_Core all comes down to testing. The version of P95 you're using isn't going to work the AVX instructions like the newer ones do (29.3). That's why they've added the offset for AVX.
As for "good" voltage well not sure what you're asking. By good do you mean better than average for the clock speed? Or just over good for the system. At "safe" voltages that chip should last you many years any way so personally I would run up to 1.35V daily as long at the temps are in check and with the power savings active the system will down clock/volt so there should be no issues
 
OP
M

MJBN77

New Member
Joined
Jan 2, 2018
V_Core all comes down to testing. The version of P95 you're using isn't going to work the AVX instructions like the newer ones do (29.3). That's why they've added the offset for AVX.
As for "good" voltage well not sure what you're asking. By good do you mean better than average for the clock speed? Or just over good for the system. At "safe" voltages that chip should last you many years any way so personally I would run up to 1.35V daily as long at the temps are in check and with the power savings active the system will down clock/volt so there should be no issues

With "good" voltage I mean something that would be a normal good voltage on an average production 8700k. Basically, what would be the expected voltage for 4.8Ghz on an average 8700k. I don't want to run the CPU on a higher voltage than necessary. Is 1.24V considered normal, good, or bad for 4.8Ghz? If it considered bad, I would spend another couple of days to find the bottom. If it considered good, I would save myself all the extra work and would move on to 5.0 GHz.

Oh, and yes I run the latest version of prime 95 with AVX as well, but only to check if the temps are in check. They are with 4.8Ghz. For 5.0Ghz I will have to use an AVX offset of -2.
 

Johan45

Benching Team Leader Super Moderator
Joined
Dec 19, 2012
Like I said I would keep moving up. You have a starting point just up the multi and test if it fails add a bit of voltage. 5.0 with 1.3V is pretty good to above normal on these CPUs if that helps.
 
OP
M

MJBN77

New Member
Joined
Jan 2, 2018
Like I said I would keep moving up. You have a starting point just up the multi and test if it fails add a bit of voltage. 5.0 with 1.3V is pretty good to above normal on these CPUs if that helps.

you mean to move it up from the 1.24V @ 4.8GHz? Even so all the stress tests I ran passed with not failures?
 

DaveB

Senior Member
Joined
Dec 18, 2000
you mean to move it up from the 1.24V @ 4.8GHz? Even so all the stress tests I ran passed with not failures?

That's not what you quoted. He said: "up the multi and test if it fails add a bit of voltage".

So do you want to OC higher? If so, do what he said and see how far you can go.

Are you giggling like a school girl at 4.8 GHz? Then you're done.
 
OP
M

MJBN77

New Member
Joined
Jan 2, 2018
That's not what you quoted. He said: "up the multi and test if it fails add a bit of voltage".

So do you want to OC higher? If so, do what he said and see how far you can go.

Are you giggling like a school girl at 4.8 GHz? Then you're done.

sorry, I misread his post. Yeah, I will go higher. But first I try to find out what is the lowest voltage I can run 4.8Ghz stable.

I already know that I can get 3.0GHz at 1.35 stable, but only with a AVX offset (otherwise the temps are too high in prime95 with avx).