I Have recently downgraded my Laptop (Acer Aspire 5516). It came with Vista Home Basic. So I have installed Windows XP Pro/SP3 Suddenly I have a problem when the system goes to shutdown or reboot it just hangs. I have the correct SATA drivers loaded. I used nLITE to slipstream them into a copy of the OS. My machine boots properly as I have the AHCI enabled in the BIOS(instead of IDE native) so I know the SATA driver is working or else I'd get the blue error screen. But as I said my machine no longer seems to shutdown or reboot properly. If anyone has any ideas on what's going on I'd be very thankful for some helpful advice Thanks!