i have a core2duo 2.1ghz with a asus P5LD2. it stopped booting windows XP from a sata drive a few days ago... tried to boot it with an ide drive from another machine which works perfectly... doesn boot either... no safe mode or nothing... it loads the first driver (a347bus.sys not sure...) and then it reboots automatically... but the machine will boot XP from a CD Drive.... and Ubuntu runs smoothly on that machine too... The problem seems to originate from some trojan i let pass even if avg detected it...