Windows 7: Overclock causing system instability?

Hey all, I have a question I'm hoping someone can help me out with. You see i've had this custom built PC for about 8 months now. From the day I assembled it, I've had my 3570k running a 1GHz overclock to 4.8Ghz. Now although I haven't done any day long torture tests on the OC, I have tested it multiple times for up to an hour with Prime 95 and not had any crashing. I have however noticed for some time that powerful applications (cad software, games, etc.) are often unstable, and sometimes my whole system loses its stability. Now the other day, I finally got fed up with all the crashing (ive already tried troubleshooting my Windows install, memory, and graphics) I lowered the clock rate down to it's native 3.8GHz. When I went back in to launch the game that had been crashing (LoL) it started fine. I then restarted it several times with no issues. Now I haven't been able to do very thorough testing at the new clock speed, but does anyone think the overclock could be the reason for all my crashing? I'll probably test this more later, but another question is, will this down clock have much effect on my gaming performance? (I game at 6000x1200 on a HD 7870, so I was thinking my GPU would bottom out long before my CPU does) Also, do you guys think i could safely bump my OC up to 4GHz without having to worry about stability? Thanks guys.

tl;dr Is a 1GHz oc above stock speed enough for system instability? Will dropping the oc back to 3.8GHz also drop my framrate in game? And is 4GHz a stable number?

The 4.8GHz OC was probably a little too aggressive to be honest. Prime95, AIDA64 or any other stressing software needs to be ran longer than an hour. I have seen instances of Prime95 running 7 hours and then showing a failure or instability. My personal method is when I first start to OC, I turn it up a good amount and run AIDA64 for 12 hours. At the end of that, I check my temps and make sure everything is on the up and up. If it is, I consider it stable. I have run Prime95 after AIDA64 just to be certain, but that may be overkill. Any stress testing software ran for 12+ hours will generally flag a problem if there is going to be one. After my stress testing, I will fine tune some options and the voltage if need be.

What method did you use to OC your system? Did you use some software that allows you to OC while booted up in Windows, or did you do it in the BIOS? A number of us on the forum have this same CPU and most will tell you that 4.3-4.5GHz is a really good OC....4.8GHz is nearing the edge in my opinion.

Also, I consider 4.4GHz to be a full 1GHz OC because the stock base clock is 3.4GHz. There are quite a bit of guides on how to OC a Z77/Ivy Bridge setup, and none are that difficult to be honest. As long as your temps stay in line, you should be able to get a nice OC........maybe not 4.8 though.

And to answer one of your questions......an unstable overclock will cause programs to not open correctly, crash, blue screen or a number of other things.

Okay thanks for the feed back. I'm still kind of mad at myself for not realizing something so obvious that I even did myself could cause problems. I did my OC through the bios, if you want to know the precise settings i would need to go check them (when i clocked back down i hadn't checked the settings in a long time). I'm thinking of setting my OC to an even 4GHz, but am a little concerned about performance. When im running games most rarely exceed 40% usage of my cpu, but when gaming in eyefinity every fram counts, and i was wondering if anyone thought scaling it down to 4GHz would hurt my FPS drastically (more than 5 or so FPS hit). However if I test at 4GHz and it comes out to be stable i'd most likely be willing to compromise. Usually the most CPU intensive things I play are games, so is stock clock enough to keep the same framrates? Or will I need to go to 4GHz? Or higher? I know thats probably a hard question to answer because it depends on the game so ill probably do some benchmarking myself. Opinions?

The 3570K at stock settings is one of the BEST CPU'S for gaming available, but I have no way to tell if you will see much of a boost in FPS if you overclock. You could find a pretty intensive game that has an FPS counter and do a repeatable run-through @ stock settings, 4.0GHz, and whatever else you wanted......that would give you the best idea of what you would need. You may see that the difference between stock clock and 4+GHz is less than 5fps.

If you can keep good temps, there is no reason why you shouldn't OC to 4+GHz. It may not help you much in games, but it sure won't hurt either......as long as it is stable.

You can run something like IBT for 5-10 passes which only take a few minutes to get a quick idea if you in the ballpark in regards to stability.
But for the true stability test, Prime needs to run a good 10hrs.

I too have seen one thats slightly unstable fail between 8-9hrs of Prime.

The problem as you know alreasy is that it isnt stable. The bad thing here is that a highly unstable OC being used for any length of time can cause system corruption.
Most likely, Vcore just needs to be increased. But temps will play a large role in how much you can.


I will say this
If you try for 4.2-4.5, the voltage requirements are going to significantly lower, and the performance difference will be minimal, especially during gaming. Most of these chips start seeing rapidly increasing diminishing returns after about a 20% OC. So thats 4.2 up 4.6ish (turbo) for a 20% OC.

IMHO, this is the ideal range due to reasonable voltage,heat and good performance increase. After this though, you need to start pouring more into it for little in return
(for most chips anyway, there are some golden ones out there)

Okay thanks for the advice kbrady and wishmaster. I think I'm going to start off at a 4.5GHz overclock and let prime 95 run all day. If it crashes out ill start working my way down from there. I think then once I find my stable clockspeed ill start measuring frame rate dependency in some games I play and see if theirs actually a difference. Sound like a plan? Or would it be better to work my way up from stock clocks until I find its limit? Anything between 4 and 4.5GHz and ill still be happy.

Well I just played a couple of games with my CPU running at stock speeds, and didn't see any noticeable framrate drops. I'm now going to start up prime 95 at 4.6GHz and let that run until tomorrow.

What is the CPU voltage @ 4.6GHz?

Currently I'm running 4.5GHz at 1.25V, but I want to see if I can set it lower.

That is pretty good actually. If you don't already have RealTemp 3.70, go ahead and download it so you can keep an eye on your temps. Run Prime95 on it at 4.5HGz at that voltage for several hours, at least 10-12. See if you have stability with those settings.