Are you using high-performance memory by any chance, like Corsair XMS, OCZ,
Mushkin, esp. PC3200? These high-end memory products often require more
voltage than the mobo normally provides by default, so it sometimes won't
boot. In such cases, you need to increase vDimm a little to make the system
bootable. Of course, this can be a catch-22, which is why I always keep
some cheap, generic PC2100 lying around, just in case. But this is just
speculation, it could be other things, but it's one thing to consider.

Also, is this perhaps a "mobile" Athlon processor? Is the PSU a quality
unit? What model of mobo?

Jim


"Grativo" wrote in message
...
I just bought a Shuttle MOBO w/ Athlon 2700+ combo. The problem is that
90% of
the time when I hit the power button, the CPU fan and the MOBO power light
up,
but I don't even get a post from the mobo. It does this even when I only
have
the video card hooked up. 10% of the time it does post and boot up
normally,
but it erases the FSB memory in the BIOS setting, and boots up at 100 Mhz
FSB
setting. However, if I get into BIOS, it go back to 166 Mhz on reboot
even if
I don't do anything and just exit. Anyone knows what is causing this?
I've
exchanged the MOBO and power supply from the place I bought this at, and I
switched out the memory, but it still does this...I'm totally stumped...

Grativo