I've done that it used to work for me in 10.4.1, but now I have 10.4.3 and when it boots and it is at the Darwin loading black screen with white text, I hit F8 and it doesn't give me a prompt to enter anything...I don't have silentboot enabled bc I see the Darwin loading screen.
::Edit--Okay I got it working, my problem was I had my ps2 keyboard going into one of those ps2 to usb converters. I plugged in a regular USB keyboard and it worked. Will update when I try to get the resolution changed. Thanks for the help and quick replies.

Okay I did '?video' at boot and all of them were below 800x600x32, I do have Vesa 3.0 according to the top of the Darwin boot prompt. Also when I type: -x "Graphics Mode"="1280x1024x32" it doesn't change the resolution.
Does this mean I can't go above a 800x600 resolution?