i5 overclock wont load windows

[matthewprince]

Hi,

Im am currently running my i5 750 at 4.0ghz (20x200) but if i alter the multiplier to 21x it wont load windows??

Any reason for that?

My motherboard is the Asus P7P55D Pro

Matt

 

[eyetrip]

You'll probably need to increase the voltage to the CPU.

 

[matthewprince]

Hi,

Well i upped it to 1.4 to do 4.0ghz , what voltage do you reckon to get the 4.2?

Matt

 

[eyetrip]

Couldn't say. It's something you will have to test as each chip is different.

Also, once you hit a certain point, the voltage required for small increases grows exponentially.

Take my I3 530 for example. I can get 3.7GHz on less than stock voltage (which is 1.175), 4GHz takes around 1.2V, 4.2GHz takes 1.3V, and never managed to get 4.4GHz stable even at 1.4V, though didn't like putting 1.4V on so didn't try for very long to get 4.4GHz.

 

[matthewprince]

Well ive dropped my voltage to 1.35 @4ghz and its stable but even at 1.45 it wont boot to windows with 4.2ghz

 

[OrphanBoy]

Yeah 1.45v is more than I'd comfortable sticking through the chip. I have the same chip and same board and 1.35v gave out far more than running 3.6GHz at 1.2v. 1.45 would be hot!

 

[matthewprince]

Well running at 4ghz @1.35 im getting very low 30's idle and mid 60's load!

 

[OrphanBoy]

Ah I see you're on water...I was considering having another go at doing it on my own build there for a second! I don't think my old 939 blocks would fit on my i5

 

[Hotwired]

Probably hit a limit on that chip.

I've had 4.2 on 1.392V: klicky

Can't remember if I checked that for stability or not.

Actually 4.2 ran for long enough to run 3Dmark06 so it was stable enough (to get the benchmark )

 

[Invictus]

you might need better cooling for other components like memory or northbridge. although the memory controller is on the cpu now, the northbridge is still a vital component.