2500k MAX safe voltage?

What about PLL?

Thanks!

Intel has verified (through their Sandy Bridge technical PDFs and online chats) that 1.52v is the max 'safe' vcore. As long as you can keep temps under control, you can go that high. Of course, keeping it lower than that would be a good idea, just in case...

Oh, and 1.9v PLL is required for stability with some of the higher overclocks. Don't go too much over that though.

just wondering.... has anyone reached 5.0 ghz yet on the 2500k with a standard cooling solution, ie water or air?

I have to say that I would be surprised if someone hasn't done so already.

So far just 4.8GHz with mine ... but I'm not done. I haven't even started playing with BCLK yet.

I'm actually aiming for 5.1GHz on air, so we'll see what happens.

arent u afraid of the temparetures at this clock speed, i mean cmon, id figure ud need a water cooling setup for these kinds of feat  

sweet tell me the results...

Intel's Datasheet says VCC_MAX is 1.52000 Volts.

Heh. So far so good at 5.0GHz with a Scythe Rasetsu air cooler and excellent case cooling. Not done stability testing though...

Subscribed.

*sigh*      

Sadly, I seem to have encountered this processor's multiplier wall. It's running at the absolute ragged edge of stability at the 50x multiplier, and no amount of voltage/setting stroking will allow for passing more than a couple hours of Prime95. And I didn't even attempt IntelBurnTest, which works the CPU harder by using most of my 12GB of RAM.

The 49x multiplier seems to be more cooperative in all ways, allowing for less voltage to help keep temps under control.

Once I do my stability testing (24 hours of Prime95 and 50 runs of IBT at Maximum), I'll start with the BCLK.

There's still (slim) hope for that 5.1GHz overclock yet ... all I have to do is hit 105MHz BCLK.  

nice, I would like to see some benchmarks of your chip at stock and 5.0 ghz in a game where overclocking improves performance... that is just smoking fast and it makes me want to push my 955 past 4.0ghz

Oooh! Can you post a Cinebench CPU run?

Source: Linky

At 4.9GHz:

OpenGL (GPU): 71.78 FPS
Reference Match: 99.5%
Render (CPU): 7.77 points
Render (Single Core): 1.97 points
MP Ratio: 3.94x

Nice!

Well ... it seems my hopes of a 5.1GHz or higher overclock have been defeated. My CPU's multiplier wall prevents anything higher than a 49x multiplier, and my mainboard's max VCCSA of 1.2v is preventing me from getting higher than 102MHz BCLK. Even that isn't totally stable.

I think I'm actually just going to go back to using the 100% totally stable Turbo 4.8GHz preset in the ASRock UEFI. All of those voltage increases aren't really worth the measly one multiplier bin gain. Plus I don't have to worry about temps. I'll probably be upgrading to Ivy Bridge or Sandy Bridge E, but I'd like to have this processor to fall back on just in case those plans don't pan out. I'll just have to be content with 4.8GHz for now...

yeah I wouldnt bother with it for now 4.8 is more than enough! but I can understand wanting to push its limits as much as possible.. 

And for reference, at stock speed (Turbo Boost enabled):

OpenGL (GPU): 54.74 FPS
Reference Match: 99.5%
Render (CPU): 5.42 points
Render (Single Core): 1.48 points
MP Ratio: 3.66x

Turbo Boost skewed the last two a bit, beings the CPU was running 300MHz faster on the Single Core test.

Some nice gains there, going from stock speed to 4.9GHz on a Sandy Bridge.

I have to say I am at 4.4 happily with my 2500k. I did the auto-OC with the ASRock Extreme4 and left it alone. Idles around 30 C and at load with Prime95 is at 58 C or so. I use a Scythe Mugen 2 rev. B cooler with a Noctua NF-P12 as the heatsink cooler.

Hello

I used 1.375v in Bios allow for droop for 5GHz, ran stable all day.
Only thing stopped me from going higher was worrying.

My 24/7 normal running is 4.5Ghz @1.3v full load 1.28v idle
Only other voltage I touched was ram set @1.5v
Prime @4.5Ghz is 60c Ambient 20C
Disabled almost everything in bios
Cores I never touched or pll

Is 1.28v too high 24/7 ie: for not underclocking/undervolting ?

MSI P67A-GD55 (B3)
2500K
CM Hyper212+
2 x 2GB patriot signature 1600 9.9.9.28 ( spd not linked)
2 x Gigabyte GTX460 soc (815/4000)

Getting Noctua and 2x4GB GSkill 1600 1.5v this week.

Longtime AMD user, very happy indeed.



Uploaded with ImageShack.us


edit; BTW genieOC sets the voltages way too high so i would watch other auto OCs as well.

At 4.2GHz Genie used more power then I did for 5GHz

not much of a point to bring it any higher than 4.5 ghz at that speed, you will already be covered for the most ridiculous gpu setup and beyond... you kind of need a purpose before you pursue a further overclock than you already have imo

Was only to see limits ( never had a bsod or freeze all the way )

I fully understand as I said 24/7 is 4.5GHz  
Poor air cooler for that overclock and at any rate.

I could wack H70 on it would be 5GHz maybe more 24/7 no worries but as you say the point ?  

4.5Ghz is my sweet spot.

thats a good 24/7 OC, never tried it but ive heard bad things about the h70 in that it doesnt perform much better than most aircooled cpu coolers, I have a hyper 212+ and it rocks

Yeah never meant to imply 212+ is not good cooler I have 2.

I think H70 would work well at 20C ambient blowing air inside as Corsair suggest
if i had air cond I would consider it.

Here in summer nothing helps everything is 35-40C to touch ...before it is turned on.

I think it is crazy to reverse the flow as most sites suggest for H70 ?

It is logical air outside is cooler then inside case why would you want to trap warmer air
to radiator and create a hotter cycle makes no sense yet respected sites do it.

Al they do is create a 150AUD exhaust fan it is better use rear for H70 intake and top of case for exhaust fans

Me <-----5.0Ghz on Corsair H100!

Really really old thread.