Have you boot installed XP on it before?
Your BIOS update is current, but last one was 2004.
I believe that the older 2003 IDE controller is not known to Windows 7 installer, so that
driver needs to be added into the installer from it's download page here:
http://support.dell.com/support/down...IM_PNT_P4_8300
Unfortunately you are not getting to the Custom drive screen where
Drivers can be added at the link, so it may require vLiting into the installer, recomposing the ISO and burning to DVD.