Is anyone able to provide a telephone number for Microsoft support? Attempting to install an updated Nvidia 790i motherboard driver resulted in a system that recognizes input from neither the PS2 keyboard nor the PS2 mouse, and after the initial Windows XP loading screen with the progress bar at the bottom, the screen is black. Apparently XP is running from the indications of the hard drive select light, and the fact that it seems to go into sleep mode if left unattended. But plugging in a USB mouse doesn't seem to do anything useful. Booting into the Recovery Console from the Windows XP Professional CD works, but I have no clue what to do to restore the system to functionality. I need the help of a professional familiar enough with XP and use of the Recovery Console to walk me through restoring the system. And I'm willing to pay for the help.