Hey guys I have a question about overclocking I can't seem to find the right answers...

Hey guys I have a question about overclocking I can't seem to find the right answers. I'm a noob at this so bear with me.

I recently bought a I7 6700k on a MSI Z170A M7 mobo and I'm going to overclock it. So far I read that the main thing I need to do is set the multiplier to 45 for a 4.5Ghz speed and change the option for voltages.


How would I go about testing all of this? I'm using CPUz to monitor the core speed and core voltages and using Prime95 to stress test.

So far I would crash or get a core failing when using around 1.25~ volts so I'm using 1.264 right now and it hasn't crashed or had any errors in the past 30 minutes.


Is there anything I'm missing that needs to be done?

Also how long do I need to run Prime95 to have my voltages for my multiplier to be considered "Stable" is the 24 hour mark a "gold standard" or something?


I'm running temps around 65~ currently.

Thanks for the help I appreciate it guys.


Picture unrelated, just using my laptop to post this.

Other urls found in this thread:

overclock.net/t/1570313/skylake-overclocking-guide-with-statistics
overclockers.com/forums/showthread.php/756757-x264-stress-test
twitter.com/AnonBabble

edit: It does sometimes jump to 1.272V according to CPUz

That's about it just runs stress tests for quite a while to see if you crash. Prime95 has a check math mode where t will see if your getting errors


I just let it run until I think it's good

Yeah thats what I read about doing to ensure it's stable at the voltages. Now I'm just double checking in case I missed anything. In the bios I edited 2 things, the multiplier from 40 to 45, and the voltages for the cup.

I just got a clock watchdog thing as we speak so I think I have to up the voltages again

Do you know what is considered an average voltage for 4.5 on this CPU? Some people have said it should be 1.25? others up to 1.35.

Don't forget to up your uncore/cache ratio

Explain please? Isn't that the "45"?

I have CPU ratio set to 45, and voltage set to 1.285 currently. That's all I touched

nah it's a separate multiplier for the L3 cache, you should be able to bump it up a little (42 to 44 X) without changing your ring bus voltage

Is that the ring freq thing? It's set on auto or 4100 Mhz.


Is it needed to be bumped up? right now I'm trying to just get 4.5Ghz to be stable and im still looking for the voltage spot for it via prime95

aye, you can normally bump it up a little without voltage change. Probably best to get stable at 4.5ghz and then refine stuff like ring bus freq

Okay. I', going to assume to try to get the CPU stable at first.

Is this all that needed to be changed? I made the multiplier a 45 and the voltage I am increasing by .05 each time until no crashing.

Right now I'm testing 1.272 according to CPUz. Does this seem too low? What should the average be close to?

around average, Gold chips will do 4.5 at below 1.2v and bad chips need high 1.3/1.4v

Earlier I had CPU loads drop to 90% after 10~minutes of running so I assumed power was too low. Is this correct?

I feel I got a shitty chip then because I'm using 1.280 - 1.272~

My Ideal speed would be 4.5 or 4.6, but I'd like to at minimum get it working properly at 4.5

you could be lucky and have a stable 4.6/4.7 with only a small voltage increase

Every one is different

Is it even possible that a 4.5Ghz runs poorly but a 4.6 /4.7 runs good?

On the side note, right now we got good temps, but here are the speeds and voltages...

4.5 Ghz @ 1.272 -> 1.280.

Should I try increasing the ghz maybe? I got a crash earlier aroudn 1.265~ after 30 minutes of running prime95

you could either go for stable at 4.5 or try to go for 4.6. 4.6 might need 1.3v or above though and that's when temp becomes a problem

I see, I got a good cooler H110 or whatever it's called however, I'd like to try to stay under 1.3 for temperature reasons as an "Ideal". . Also from what I read I'd like to avoid going above 1.35 as my limit.

As a final question, how long would you run the torture test on "Prime95" to state it's stable?

24 hours?

I'm really hoping my chip isn't poo and can handle 4.5 under 1.3

I avoided using prime in recent years due to it turning haswell into a flaming mess temps wise. don't think skylake suffers from that though so i'd go with the blend test for 24hrs+

Ok sounds good, does a 4.5 under 1.3 sound realistic?

The highest temp I seen so far is 69C which is well in the safe limits ( I think?)

(On Average)

I'd say under 85-90 when under prime95 or similar is fine for temps as you are never likely to see temps that high under normal use. 4.5 under 1.3 should be doable as long as you don't have a crap chip

Alright thanks so much for all the help man, I appreciate it. Sometimes I get people just flaming instead of giving an actual response. Kudos to you man.

The cooler is good, I mean I got no complaints its a 2 x 140MM watercooler thing so it handles temperatures well.

I think we are getting closer to the "Right" spot because last test it took about 30 minutes to crash and right now it's been about... 30-40 without any hiccups.

45 minutes in,

1.28 Volts and 4.5 ghz according to cpuz. This is the longest I got it running yet :)

60~C

Current version of prime95 is not suitable for stress testing because it uses some extensions that are gimped on Skylake.

From my research overclocking my own 6700k, a lot of people recommend using this x264 batch script to stress test over prime95 since it's a more realistic scenario than crunching prime numbers:

overclock.net/t/1570313/skylake-overclocking-guide-with-statistics

If you still want to use prime95, get 26.6 since apparently that one is still good for Skylake.

Seems like the absolute max you want to go for air cooling is 1.35 V, but you should be able to get 4.5 at around 1.3 V. Under full load, max temps of 80 are ok.

Hmm...is it still a good indicator though? I'm not the smartest at these things.

I'm using liquid cooling so I think I could push above 1.35, but I'd like to stay under 1.3 or at for 4.5 Ghz (If the chip allows )

It's probably just overkill, and will raise your temps 5-10 degrees higher than anything you'll actually experience in a real-life scenario.

Well right now I'm running...


1.28 volts @ 4.5 Ghz with about 55-70 degrees ( varies )

It seems to really like 60C though...

seems to hang around here

update, bsod, watchdog error -.- I'm pushing the voltage now to 1.288-1.304~ how bad is this chip?

It lasted about 2 hours before crashing so am I getting closer to the sweet spot?

Going to attempt 4.6 @ 1.325...

I find it easier to just go for the max voltage you're comfortable with, and see what clock you can get stable. Then drop the voltage until you get instability and you have an idea of where you need to be.

Do you think there's a point in going for 4.6 with my build or stick with 4.5?

I'm starting to think it's pretty bad if I'm crashing with the previous set up.

It's up to you based on what vcore you're comfortable with. It's a 12.5% increase versus a 15% increase, so what's that extra 2.5% worth to you?

That's true I guess, I'm going to try running it at 4.5Ghz @ 1.295 volts then...


This is pretty bad isn't it? Am I getting closer though? My last voltage I hit about 2 hours which is the longest so far ( Last was 1.28~ )

It's not bad. Most Skylake OC reviews indicate a sweet spot of 1.3 - 1.35 vcore for max overclock before you get diminishing returns with vcore increases.

Odd thing is, my mobo says it's 1.3V right now but according to CPUz its using 1.288V.


It was running pretty fine for 2 hours on 1.28 earlier so I'm curious if I'm getting close to it.

I just feel it's a shame because I was expecting 4.5 under 1.3 so I could potentially push 4.6 with under 1.35 but I guess I'm going to end up needing 1.35 just to run 4.5

Your voltage will always drop under load a bit from what you set it to. The difference is called Vdroop.
If your mobo has a setting called LLC (load line calibration), you can use that to compensate for Vdroop, and it might make your OC a bit more stable. Depending on your motherboard, you'll have various levels of LLC you can set, higher levels mean the board will raise the voltage under load to reduce vdroop. Monitor what your CPU-Z says after you try it.

Also, no use fortune telling with these things. There's a reason getting a stable OC takes time and lots of stress tests.

I would really suggest you just set your vcore to 1.35 right away and see if 4.5 is stable. If it is, try 4.6. And so on until it's no longer stable. Then go back to your last stable clock and start reducing vcore until you hit instability again. Now you know where your vcore needs to be.

So should I try going 4.6 Ghz @ 1.35 volts now? Then going to 4.5?


I didn't expect it to be easy, but damn this is a pain

Just be thankful this isn't 16 years ago. Overclocking used to be much more painful. Hell, be glad you're not doing this with jumpers like in the 90's.

Have you gotten 4.5 stable yet at any voltage?

Neg. been climbing up the voltage ladder with the 4.5

So start with 4.5 @ 1.35 V. If that's stable, you can bump it up to 4.6 and see what happens.

God damn if it crashes here with this im going to cry lol

just for reference in case this takes a few days,

Lets assume a few scenarios.

A: What should I do if it crashes with 1.35?


B: What should I do if it's stable? Should I do the following then.... Test @ 4.6, if it crashes, hop back to 4.5 and bring down voltage to a crash. ( Is this correct for B?)

(A): Check your vcore in CPU-Z. If it's still under 1.35 V, you can do two things:

(1): Play around with LLC. Higher levels should result in less vdroop under load, and so your actual vcore in cpu-z will be higher even though you haven't increased vcore itself.

(2): Raise vcore until you're at an actual 1.35 V in CPU-Z.

I would start by trying (1) first. Check to see what effect various levels of LLC have on your vcore at load.

(B)
Yes, go up a clock until you crash. Then go back down to your last known stable clock. At this point you reduce voltage by small steps until you get a crash. Your last known stable voltage is your sweet spot.

Alright I set my mobo to 1.35 and CPUz reads 1.336 -> 1.344~ roughly

im not really liking these temperatures though, 76 at a peak right now.

It hovers @ 1.344 85% of the time. LLC might not be really needed.

Yeah that's a very low vdroop (which is good). You probably have LLC set to auto by default, so it's probably on to some extent.

The 6700k starts throttling at 100 degrees, so 76 is really not bad at all. 80 and under I wouldn't be worried about.

Alright well I'm going to leave this running overnight and I'll make an alarm for 4 hours ahead to see if it's still up.


24 hours without a crash would be ideal using prime right?

I really wouldn't use the current version of prime, man. I did a lot of reading on Skylake overclocking the past few weeks, and everybody recommends against it. Use this x264 stability test:

overclockers.com/forums/showthread.php/756757-x264-stress-test

If you're still dead set on prime, then at least use 26.6

Wrong link.

overclock.net/t/1570313/skylake-overclocking-guide-with-statistics

Alright well I'll post an update in a few hours, I'm going to take a nap and see what happens. I really hope this is stable for the 4.5.


In all honesty I guess 12.5% increase vs 15% increase is good enough since the extra temperatures for a 15% isn't worth it imo.

I'm just trying to get a 4.5 to run at the lowest possible voltage while being stable.

I really just want to stay as close as possible to 1.3 :\

If you can't get 4.5 stable at 1.35 you got pretty unlucky in the chip lottery. I got mine to 4.7 at 1.35.

For real, I mean the thing is I haven't explored the 1.3-1.35 range yet. I fully explored 1.2-1.28~ and it's not there

My last failure was a Vcore of 2.8 @ 4.5 GHZ and it took 2 hours on Prime to fail.

So I feel we are "Getting" somewhere.

1.28***

For all I know, we might be able to get a 4.6 @ 1.35 which would be my top top goal, but I'll settle with 4.5

I think the fact we lasted that long on that voltage earlier, it might be able to grind out 4.6 @ 1.35 ( Optimistic as shit )

Either way before I go to bed for real now haha, I'm going to aim for a low voltage 4.5 for now. I'll see if it's stable overnight and adjust if it's stable.

Cool, good luck, man.

Yes.