Instability with Overclock 2600K on Gigabyte Z68X-UD5

[Alec246]

Hey guys!

I was crazy testing all I could to find out why my PC was restarting during Gaming Sessions. I would be playing, the temperatures OK, and it would suddenly restart. It took me some time to get that the reason for this was the OC of my SandyBridge 2600K. I made a setting to run it at 4.4Ghz using Normal Vcore ( Set Automatically by the Gigabyte Z68X-UD5-B3 ) and an Offset of -0.050V. Prime95 for Hours and it's stable.

Luckly I found a game that can make my PC crash in a matter of minutes, so it was easy to test what was causing this. What I did was load a Stable 4.4Ghz setting I had saved on my Bios for a Locked VCore. The PC runs beautiful.

Then I went to check with CPU-Z what was happening with my Vcore during gaming, because I tried removing the VDID to 0.0V and it still crashed. What I found out is that the game wouldn't ask too much of the CPU, and the 2600K would go from 4400Mhz to 1600Mhz pretty often, and the VCore would drop from 1.29V to 0.9V, and get back up, and it was probably one of this fluctuations that crashes my PC.

So, I ask for your opinion on what can I do to get my stability back? I like setting my Vcore to Normal since 95% of the time my PC is Idle, so there's no need to push hard on the CPU, but unfortunately, I don't know if it's Gigabyte's or Intel's fault, or maybe my own, it's not holding stable.

Thank you for your time!!

 

[Carfax83]

Try disabling the C states, with the exception of C1E. You could also try using load line calibration to less the effect of Vdroop.

Another option of course, is just to use a fixed voltage. Personally, that's what I use on mine. The offset option seems like just too much trouble to go through just to net a few watts of power, and I've noticed that the voltage is very unstable with offset turned on and prone to spikes and fluctuations.

Mine is set to 1.285v, and during load it drops down to 1.25 with LLC enabled.

 

[Alec246]

Yes, I'm considering fixed voltages here. What I don't like to use if LLC, first, not too good on your CPU I hear, they send nasty spikes sometime, I don't like that much, second it's tough and time consuming to find the right one that isn't overkill, making the CPU suffer more than it needs to.

It is very unstable indeed with Offset, at least on my Rig, maybe the newest generation from Intel has gotten smarter!

Thank you for the help!

 

[Carfax83]

Yes, I'm considering fixed voltages here. What I don't like to use if LLC, first, not too good on your CPU I hear, they send nasty spikes sometime, I don't like that much, second it's tough and time consuming to find the right one that isn't overkill, making the CPU suffer more than it needs to.

LLC isn't dangerous on these new motherboards. Back in the socket 775 days, I would have agreed with you though.

The new motherboards have different levels of LLC you can apply. For example, I have mine set to level 3, or medium. It's very safe, and will allow you to use a lower fixed voltage than you would ordinarily be able to because Vdroop is lessened.

Never use the maximum level, unless you know exactly what you're doing.

It is very unstable indeed with Offset, at least on my Rig, maybe the newest generation from Intel has gotten smarter!

Yeah, it's like that on mine too. By using offset though you only save a few watts of power. Not enough to justify spending all that time finding the right settings imo..

 

[JimmiG]

I've always ended up using fixed voltages with my overclocked AMD and Intel CPUs for stability reasons.

It doesn't mean your CPU will always run at max TDP and use hundreds of watts. There are still massive energy savings when the CPU is idle, compared to full load (just compare the temperature at idle and full load with fixed voltages).

 

[inf64]

Any update? Did you find out what was causing it?

 

[coffeejunkee]

I'm pretty sure it has nothing to do with offset or static.

A much more likely cause is that you are trying to run 4.4GHz at a lower vcore than stock (the 'normal' setting locks the vcore to it's original value). These chips are good clockers but that's asking too much.

Prime/Linx etc are kinda meaningless with these cpu's. Games/general activity catch instability much better.

 

[Alec246]

Well thank you for the input!

Pretty clear now that fixed Vcore is the only way to achieve true stability!

I will experiment with LLC then, the fact that I will be able to drop my Vcore is encoraging. But it's a matter of finding the right balance.

About Stress Test, it's good at generating heat, but for really testing your CPU, nothing better than a good game.

The Game that crashed my PC in 2 minutes is the one called Spate, it's a Beta from the IGN Next Game Boss show.

http://www.ign.com/wikis/next-game-boss

Maybe you guys can test your rigs with it too!

I will let you know once I get to a nice stable Bios setting.


Oh, one more thing. This Gigabyte TouchBios, is it good enough to allow me to not need to restart my PC everytime I need to change some setting?

Thanks!

 

[Alec246]

LLC 4 Vcore at 1.30V in the Bios. It's running Linx Stable so far. What do you think guys, should I go to a higher LLC to try to lower my Vcore, or is this good enough? The thing I don't like is that it's 1.30v during Idle, not good for my PC.

I know that LLC 6 would be the maximum safe value, but I don't want to risk it, although my CPU have a lot of Vcore to spare until getting to the dangerous levels of Voltage, since my OC is only at 4.4Ghz.

Let me know what you think. Also, please give me some tips of nice Stability tests other than Linx,Prime95, etc. What's the best Video Transcoding technique to test the CPU? And which game is toughest on your PC?

Thank you!

 

[Carfax83]

LLC 4 Vcore at 1.30V in the Bios. It's running Linx Stable so far. What do you think guys, should I go to a higher LLC to try to lower my Vcore, or is this good enough? The thing I don't like is that it's 1.30v during Idle, not good for my PC.

1.3v is still low. Enable all of your reduced power states, and make sure EIST is enabled as well and you won't have to worry about a thing.

On my motherboard, I have 5 settings for LLC, with 1 being the highest. How many settings does your board have?

Let me know what you think. Also, please give me some tips of nice Stability tests other than Linx,Prime95, etc. What's the best Video Transcoding technique to test the CPU? And which game is toughest on your PC?

Thank you!

Personally I never use stability testing software like Linx, Prime95 etcetera. They put too much of an unrealistic and very focused workload on the processor which does nothing for proving stability other than increasing power usage and temps.

I use games for my stability testing, and right now, Crysis 3 is the best game to test your overclocks with imo. The Welcome to the jungle level in the early stages of the game will load your 2600k to almost 100% due to the amount of physics and animations on the thousands of blades of grass..

The whole game really stresses CPUs though. I've seen my 3930K @ 4.4ghz hit as high as 90% usage at times, which is incredible. Ordinarily it wouldn't hit that high of a usage, but I have the maximum pre rendered frames set to 3 in my driver control panel, which increases CPU usage during gaming (and makes games noticeably smoother).....at least in my experience.

 

[tweakboy]

Probably its the voltage,, raise it up a bit and keep testing. gl

 

[Alec246]

My Gigabyte has 10 levels of LLC. Level 6 is the one that matches the Vcore under load to the one you set on your Bios from what I read. Level 1 is the weakest and 10 the crazy high.

Reduced power stages you mean the one that slows the CPU to 1.6Ghz when it's not being used? If so I think mine is already On.

I Have Crysis 2 here, It should be pretty tough as well, don't you think? Maybe I'll think about Crysis 3 for this purpose, although I really don't like this game, too much graphics, not enough fun.

Thank you!

 

[Alec246]

Just had multiple reboots using my Stable 1.33v 4.4Ghz while playing Left 4 Dead 2 with friends. Don't know what else to do, this Vcore should be high enough for stability...

Maybe it's some other voltage that's not good enough? No ideia..

 

[Alec246]

Wow... No Idea what is happening.

Using the Stock Clock 3.4Ghz at Auto Voltages, my PC also restarted. I'm testing using Crysis 3. I noticed that if I Alt Tab back to Windows when the game is opened, is often an instant restart.

I have no clue what might be causing this! It seems it's not the Overclock.

 

[nanaki333]

just curious.. do you have the most up to date bios for your motherboard?

 

[Alec246]

Yes, F10 is the most current one. Although it's over a year old.

 

[tweakboy]

Hey nanaki333 are you going to buy a 4960k Ivy Bridge E 6core12threads on all 3 models coming in September 24th.

Ivy E is faster then any haswell in 2013. In 2014 haswell E comes, 6core12t in 2014.