Live CD works, boot from HDD (startx) shows no video
I am using the onboard video from my Asus P5L-MX motherboard. I just installed BT5... I've only ever muddled with Linux CLI but have used Ubuntu and Fedora on a few other machines. I have my machine hooked up via VGA to a TV. When I boot from the CD, it works fine. It also works at the CLI upon boot from the HDD. However, as soon as I run 'startx' my TV/Monitor reads 'Invalid Format' - I'm not sure how to get any logs to find the driver I need (I believe it's Xorg logs I need, is that right?).
What can I do next to troubleshoot?