vista 5456 x64 blinking cursor

Hi there, just tried installing Build 5456 x64 on my machine. After the initial setup, my system restarts to complete installation... about four minutes in, my computer yields a black screen with a blinking white cursor in the top left corner. Leaving it for any amount of time does nothing, and there is no apparent drive activity. Restarting the computer boots it into the Vista installation, and then it gives a simple black screen with no cursor... and no drive activity. Safe Mode only tells me that I have to restart into normal mode to complete installation. Any insight? System specs are below. This is not being dual-booted with any OS... clean install, only OS on the box. Thanks in advance.
Cheers,
MadHatter ----------
Pentium D 820 (2 x 2.8 GHz) 2 GB PQI Turbo DDR2-667 2 x 74 GB WD Raptor in RAID 0 on PCI Silicon Image 3112 Controller ATI Radeon X1900 XT Intel D945PSNLK system board