Why ? You already have Slic 2.1 in bios flash utility included in P5E3-1503_SLIC5.rar - AFUDOS engineering edition
It was the first thing I tried. It's there, but xp doesn't "see" it. Maybe I should try flashing a BIOS made for the ECS K7SEM, that is the same motherboard only sold under the Elitegroup brand.