sometimes when i load win7 show me blue screen unmountable boot volume,boot.ini not corrupt,i don't have UDMA option to change in bios,i tries use scandisk for bad sector, to fix any error & use startup repair but i can't find any error to fix it seem my hdd working fine.any help?? http://www.toshiba.ca/web/product.grp?section=1&group=223&product=5616