ThanK you. Fernando. In the bios there are two ways to put the modo.cuando is placed in defaults of the bios is set to SATA ENHANCED and has since AHCI0 in the hard disk and CD / DVDROM in AHCI1. In this way I can start the hearing that the windows came with the laptop. in order to use the xp what I have to change the bios to SATA COMPATIBLE. here puts SATA0 as the hard disk and CD / DVDROM as SATA1. AHCI mode when it leaves me to install the OS XP, it recognizes the hard disk and can start installing XP, the problem comes when you restart to complete installation, no longer recognizes the hard disk (I guess that is), jumps the blue screen error 0x0000007b