We use a lot of these at work running Win XP. Had the same problem and couldn't move forward on the BIOS updates, until we realized that verion 1.5 and 1.53 change the SATA from IDE-Compatible to SATA-AHCI. As soon as you upgrade the BIOS hit F2 on the reboot and make sure to keep your original SATA device settings under "Installed Devices".
Otherwise if you choose to upgrade to Windows 7 as I did, then first change it to SATA-RAID (which is recommended by Intel) and includes the AHCI extensions that the supported Operating Systems like Win 7 can take advantage of. If you try to switch the SATA type once an OS is installed, be prepared for a lot of Error 7B, can't boot, etc.