Overclock failure, please help.

hey guys,

i have an old e8400 and for some reason i cant get it any higher then 3.6ghz. i know these chips are capable of 4.0+ so i am a little comsufes as what to do next.

i can get past the post when upping it to 3.9 but then just before the windows logo would normally come up it says i need to boot from C.D. when re-entering the bios my hard drive isnt even recognised.

is there anything i can do to get my hard drive stable again, with some voltage tweaks or something??

i am currently running:

core2duo E8400
asus P5KPL/1600 mobo
4gb of ddr2 800 mhz

this mobo dosnt really have many options but the 3.9ghz settings are, CPU freq: 433 x 9, ram @ 800mhz. everything else on auto.

any help is much appreciated.

bit of a strange one, some things I would try:

Flash the BIOS to the latest version for your motherboard

Try the HDD in another SATA port, soem ports may run off a different controller

Maybe the overclock isnt stable and so can't access/load windows, try upping the Vcore slightly if its safe to do so.

Myabe a small bump in the southbridge voltage? Not sure on this one, haven't overclocked s775 in along time.

Ok cool, just looking through some google results and some other people have had the same issue, but I cannot find a resolution my google skills fail me.

I would try giving the ICH the smallest bump in voltage, it controls things like PCI, USB, IDE, SATA...ETC..

Let us know how you get on after raising the Vcore.

To add, I can not find any ich option.

3.7 is my limit by the looks of it. Any frequency/voltage increases past this and my hard drive won't boot windows.

Thanks for your help. :-)