I have a wierd problem.
My dad has a p4 pc, gigabyte ga8-simlp socket 478 mobo, running a 1.8GHz northwood cpu. I got hold of a 2.4 about a month ago, banged it into the pc and started up... pc would hang all the time etc... got ANOTHER 2.4 out of a working pc at one of my clients. swopped, same problem.
What I have done so far: Checked the cpu support list on gigabytes site, mobo supports 2.6northwood. Updated bios to latest on the site. removed all the extra drives + cards out of the pc to check if it is drawing too much current out of the psu, also tried another psu. tested both chips in another mobo and both work fine (even ran a prim95 for about 15 mins each).
OK you updated the BIOS after that enter into the BIOS (should be the delete key) See if there are options for auto detecting everything it may still be set for the CPU and your problem sounds like a voltage one...
Mobo is jumperless, and actually picks up the cpu correctly, ie 24x100 the multiplier is locked, as is the voltages, can only view voltages in the bios, no place to change like in the newer/enthusiast mobos.
As far as the voltage thing goes, the difference is 1.500 for the 1.8ghz and 1.525 for the 2.4 if i remember correctly.
Is there someting like clockgen for changing the voltages as well? or even a bios hack to enable voltage adjustments in the current bios?