Boot failure! Possible PSU problem! (HELP!! me)

This is a serious and urgent matter. I need to know whats exactly wrong with this system I built for a friend. Its got an XP1600+ and Abit KR7A-RAID with a generic 300w PSU.

Symtom= Computer fails to boot to bios when I set the AthlonXP @ 1600+ (1.4GHz) in bios. If I dont do this, everything seems to run almost ok, (DEFUALT cpu speed when cmos is cleared is 1050MHz (10.5x100). But in WindowsXP installation when cpu is @ 1.05GHz, the computer hangs when its searching for Network installation.

@ 1.4GHz, its impossible to even get into the XP installation setup.

I'm REALLY SUSPECTING THE POWER SUPPLY TO BE THE PROBLEM!

When I underclock the processor, booting to the main bios boot screen is 100% garanteed. But as soon as I set the processor back to 1.4GHz (XP1600+), the computer wont even bootup!, it just sits with the monitor having no signal . AND, screwing with voltages does nothing or makes things even worse! the system will definatly not boot with 1.85V VCORE in BIOS @ 1.4GHz


Last but not least, the 5V voltage bounces like crazy between 4.87~4.91V, WT Heck!?????????

all help is gladly appreciated!
thx in advance

what motherboard is it?


EDIT: doh lol looks like i missed that part i see now

Ok, I am unfamilar with that mobo, but wonder if the bios needs to be flashed for XP support? I think it that it couldn't hurt to post in the Abit mobo topic.

Sorry I can't be of more help, but that problem is sort of perplexing...

Try it with another power supply and see if that is it. here is a site with great info on the KR7A. Paul's FAQ . hope this helps.

try a different stick of memory u could have a bad stick

bad stick of memory?, never thought of that, maybe thats it?

Installed is 512MB (256 x 2) of crucial PC2100. Both sticks check in OK @ boot when I'm running @ 1050MHz.

man, this is a messed up situation

I'm lost

try running them individualy and see if u can get it to boot at 1.4

Try Ram Doc to test your memory it loads from a floppy....

Thankyou everyone for your replies, it turns out it was the PSU!

Enermax 430W cured the problem!

But a new problem has emerged! The CPU temperature is outragous, 66C MAX!, Why is this? I got the Thermaltake Volcano5 on there.

The only thing I can think is doing it is maybe the heatsink isnt sitting properly on the processor?