I recently got a new SandyBridge i7 2600k and Gigabyte Z68 m/board. On the advice of a friend, I bought a CoolerMaster v6 cooler and tested the overclock with Intel's own tester until I got to 4.5Ghz. The max. temp under load was around 60c.I left all the other settings on Auto and just increased the multiplier to 45 (x100).

It ran stable for 2 weeks, then fried the CPU with no warning.

Luckily Intel replaced the CPU under warranty, with a warning not to overclock again!!

If I do try again what is the best way? Should I lock the voltage to standard and increase the clock until it becomes unstable.

Any help will be welcome.

I just want the best out of FSX.

I probably know the cause. If you put your voltage on Auto, your mobo might increase the voltage to well above 1.50V, I've seen this myself, I ran 4.5 GHz and put it on Auto, and it increased the voltage to 1.55V, while I actually only need around 1.34V.

 

Download the following programms:

 

CPUID CPU-Z

CPUID HardwareMonitor

 

WIth these two programms you can check your CPU speed, voltage and tempatures. If your tempatures on full load don't go above 75C, and if you don't exceed 1.40V, then it's impossible to damage your CPU by overclocking it. Maybe after 5 years it will be dead...

 

Make sure that you watch some good tutorials first, putting everything on Auto is not the way to overclock. You whole lot more needs to be adjusted, just to name a few things: load-line calibration, phase and duty control. VRM frequency, CPU current capability, spread spectrum (disabled), all power savers off, Internal PLL overvoltage, and of course your VCore, VDRAM, VCCIO, etc.

and it increased the voltage to 1.55V

 

:o

Quite improbable that your CPU got fried that easily. It must have went WAY over 1.5 to be fried in such a short time. And possibly went way over 60c when you weren't monitoring.

The fact is, when overclocking, settings on Auto are bad idea.

 

You boot once, clock is going to be 1.4, then you just reboot and voila, mobo thinks you need more Vcore, and shoots up 1.6 into it. I've seen it happen here (but mine really did live through 1.6V). With a decent cooling like a watercooling, where the chip can't be overheated that fast that quickly, you have to lock your settings. All of them.

 

I would suggest you don't go overclocking that carelessly ever again, if you ever decide to overclock again. You must know one thing though: overclocking is always a risk.

 

There are numerous tutorials how to overclock on the net, and we can help you a lot too, I'm also quite knowledgable overclocker, coming down from couple of generations of Intel overclocking...

 

then it's impossible to damage your CPU by overclocking it.

 

Erm, no. It's always possible to damage the CPU by overclocking. Going one mV over the spec can damage the CPU. It's just the thing of probability. That is one of the rules of overclocking. Otherwise it wouldn't be called a risk.

 

Only you have to power to decide how far you are able to go with it.

I agree on never OC using auto OC profiles or by leaving all settings on auto except the multiplier. The bios has a tendency to use inappropriate volts to gain stability.

 

I saw a Asus Gene-Z running the ram at 1.7v+ and CPU at 1.5v+ for a simple 4.5ghz OC.

 

As Arjen said read some guides and do it by hand. It is pretty simple once you read a few guides. OC'ing is not as troublesome or a PITA as it use to be.

 

Here is one that should get you to 4.5

 

http://www.overclockers.com/forums/showthread.php?t=693613

 

Test for stability (Prime 95/IBT) and watch your temps (HW Monitor/RealTemp). Then adjust volts for lowest possible while maintaining stability.

1.7v+ and CPU at 1.5v+ for a simple 4.5ghz OC.

 

*gasps*

Thanks Guys,

 

I finally decided to try another route: I disabled PLL and set the voltage as locked to the Intel spec. Then increased the Turbo max to 40 on each core.

This has resulted in a CPU that lowers its speed automatically, as in the original Turbo boost/SpeedStep but goes to 4Ghz under load.

Ian how did you lock the voltage? My mobo just has +0.0000 for the vcore. Its not like i can lock it at 1.40 or anything.

Airforce

On my mobo (Gigabyte GA-Z68p) if you alter PLL, it gives you the option of disabling, which limits the CPU voltage to the max. allowed by Intel (about 1.3)

but with the power saving options left on Auto, it can drop when not needed.