I've installed a few different linux distros before, no trouble.

I just installed Vector 5.1 yesterday. It installed with no trouble, and worked well. I shut down normally, booted back up to text mode, entered "startx" and the screen went blank - and stayed blank. Nothing I could do would get me out of it, I tried ctrl-alt-backspace, and ctrl-alt-delete. After I re-started, I tried again, and got the same results. I tried chosing linux-gui from the menu, and got the same results.

My system: AMD 1600+ (1400mhz) 500mb ram. I have two video controllers, a built in AGP Tident Cyberblade with 8MB vram - which I don't use; and a PCI NVidia GeoForce with 128mb vram. I went with PCI because I don't have a AGP slot. I use the nvidia card because I couldn't find decent drivers for built in card, I was getting bad tracing.

Any clues in /var/log/XFree86.0.log or /var/log/Xorg.0.log (depending on your X server)?