VGA isn't working

I brought home the computer I built at school and hooked it up to the television I use for my home PC, it shows the boot up process up until the windows password screen. I'm a bit bewieldered at what could be the problem considering it actually displays normally up until that point. The OS is windows 7 if that helps, any suggestions?

Thanks,

Probably at the wrong refresh rate or resolution. Can you boot in with video in safe mode (F8 at startup).

Actually I did a cold boot and started it in safe mode, it worked--now I just need to tweak the resolution

I've tried all resolutions, frankly I'm pretty stumped--which is annoying considering it will probably turn out to be some super minor fix. The tv is whichever of the two that is the least impressive, 1080i or p can't remember which.

Edit:

Actually the tv is a 720p, and even in advanced settings this system seems to have very few resolutions. Unfortunatley I don't see anywhere to type my own, kinda new to Windows 7.

The card is an: nVidia Geforce 8400 gs. The tv is an Insignia 720p 26". OS is windows 7. Still in the dark, especially since it works fine until the PW screen to get onto the desktop and will boot in safe mode perfectly.

This tv has ran like... 5 or 6 other systems without even needing to be tweaked, everytime I just hook up the VGA and it works. Don't know if there's some new type of software or hardware that's not compatable, but I wouldn't think that there would be.

Ima haul it to class and troubleshoot since I gotta leave in an hour, theoretically if all else fails I can just have my instructor fix it. haha Just trying to do it personally for more hands on practice. I appreciate all the advice everyone.

thank you,