Upgrading XPS710 from XP to Vista

Trying to install Vista on my XPS 710, which came with XP installed a couple of years ago.  The installation process hangs at the point where the system reboots, and I'm forced to shut down and go back to XP.  I've downloaded the latest BIOS update (1.4.1), and I'm sure the problem is related to having the wrong versions of various drivers - but I'm unable to get to the point where I can download and install the Vista drivers.  I've searched DELL support and haven't been able find a solution, which is surprsising, since I'm sure others have experienced similar problems.  Can anyone help me out with this?