this is a weird one..
shuttle sn25p
3000+ winnie core
2x1gig Kingston DDR 400
started w/ a 2005 bios, updated to newest, then to second newest...
w/ the 3000+ installed, it will boot up and run fine w/ the 2g of RAM... If I try to upgrade to either a 3700+ SanDiego or an X2 3800...