My best suggestion:If you want your CPU to last a long time, I wouldn't go past 1.4V (Volts). Just put your VCore on that. Then raise the multiplier, and see how far it wants to go on 1.4V, it might make it to 4.7GHz, like mine, but it also might make it to 4.9! Keep your hands off the Base Clock! Also raise the Load-Line Calibration to High or Ultra High, put VCCIO voltage on 1.1V, CPU PLL voltage 1.9V, DRAM voltage on whatever is specified by your RAM. Turn all power savers like EIST, C1E, C3 and C6 off! BEFORE you attempt anything, make sure you have proper aftermarket cooling, luckily Sandy Bridge CPUs don't run that hot, so a cheap air cooler will do more than fine. I have the Scythe Mugen 2 REV B, and my CPU has never exceeded 65C on full load. Also download CPUID Hardware Monitor to check you temps and voltages, also download CPUID CPU-Z to check you voltage and to check if you CPU is running at the speed you set it too.When people try to tell you that overclocking will damage your CPU, then that's complete nonsense, BUT ONLY if your temps are not too high (stay below 80C), and when you don't exceed 1.4V too much. Instead specifes 1.52V for maximum safe voltage, but there are plenty of people which had their SB running on that and died within a matter of weeks.

For an initial overclocking to max 4,2 ghz do I need a good cooler?I don't know what cooler I have installed but it is the standard one that goes with the computer.

Yes, you need it.I wouldn't even try with the stock cooling system, it has a really poor performance and is not designed for OC purposes.I suggest you a CoolerMaster Hyper 212 + -please note the "plus" as the regular version doesn't work with this socket-.

Iam currently overclocking my i7 processor. Problem is that i cannot go past 3255mhz. The PC shuts down then. Attached a screenshot.Anybody a idea ?.

I have mine (i5 2500K) OC-ed to 4.0. Which isn't much for the chip, but I see significant changes in FSX. I started at 3.7 after a while went up to 4.0 with the ultimate goal in mind a steady 4.+ (3,4,5) But seeing how FSX performs rigth now I migth stay with 4.0 And it's not all about framerates (althought important) but the overall performance and stability.

Iam currently overclocking my i7 processor. Problem is that i cannot go past 3255mhz. The PC shuts down then. Attached a screenshot.Anybody a idea ?.

Raise your core voltage.

1.4v vcore is really high for a 24/7 setup imo. I keep mine below 1.35v at all times

Raise your core voltage.

1.4v vcore is really high for a 24/7 setup imo. I keep mine below 1.35v at all times

I will try to keep it below 1.35v. Just for safety. Is it possible that overspeed protection in the bios has anything to do with it ?

1.4v vcore is really high for a 24/7 setup imo. I keep mine below 1.35v at all times

I agree, so do I.No two processors are the same, btw, at a certain point you will hit a wall, some hit that at incredible speeds, others a bit less. But always make sure you keep within safe limits with voltage etc, otherwise you might end up with nothing. With a new porcessor build it up slowly, let it run at 3.5 or a bit higher for a while before you atempt the next step. And above all check FSX, if you get good results, even if you're not at 4.0, keep it. Because in the end it is a good performance that counts, not how high can you get.

So would you guys reccomend me turning down from 4.8GHz with my 2600K at 4.45 volts or is that fine if I have an H80 for cooling?

So would you guys reccomend me turning down from 4.8GHz with my 2600K at 4.45 volts or is that fine if I have an H80 for cooling?

Surely you don't mean 4.45 volts. I don't think that's possible. I'm pretty sure you would have a fire at that voltage.

 

If you mean 1.45 volts, that's only going to reduce the life expectancy of your chip a little I would think, but not severely. I have mine at 4.6 GHz and it runs stable at 65C on Prime95 and 1.334v Vcore and I get very good performance in FSX. I went up to 4.8 like you have yours and was at 1.455 and turned it back to 4.6 because the performance difference in my eyes was negligible between 4.6 and 4.8.

Surely you don't mean 4.45 volts. I don't think that's possible. I'm pretty sure you would have a fire at that voltage.

 

If you mean 1.45 volts, that's only going to reduce the life expectancy of your chip a little I would think, but not severely. I have mine at 4.6 GHz and it runs stable at 65C on Prime95 and 1.334v Vcore and I get very good performance in FSX. I went up to 4.8 like you have yours and was at 1.455 and turned it back to 4.6 because the performance difference in my eyes was negligible between 4.6 and 4.8.

1.45, sometimes I wonder what I type, the reason I keep it at 4.8GHz is because I do lots of 3D Modelling and renders and stuff and every bit of power helps get those done quicker.

Short of absolutely conclusive lab tests, I like to consider 1.4v a max long-term vcore for sandy bridge. I've overclocked a half dozen or so an they all hit their oc wall with vcore around 1.35-1.4v. Any more than that (and I've been up to 4.8GHz) and its just additional heat/degradation in my experience.

Heat isnt the biggest problem when it comes to high voltage, as most modern chips have built in overheating protection. They will shut themselves down to prevent damage. However, the voltage itself can reduce lifetime, sometimes drastically.

Short of absolutely conclusive lab tests, I like to consider 1.4v a max long-term vcore for sandy bridge. I've overclocked a half dozen or so an they all hit their oc wall with vcore around 1.35-1.4v. Any more than that (and I've been up to 4.8GHz) and its just additional heat/degradation in my experience.

 

1,4V is also my personal finish line. I´m currently on 1,36V stable for 4,5 GHz. I could go a bit higher but I don´t see any sense for maybe 1 FPS more but an overall shortened CPU life.

I have overclocked my i5 2500k finally to 4,5 ghz.

I have not touche the Vcore voltage but everything runs fine.

Should I increase the voltage anyway?

 

Thanks,

Christos