Windows 7: Constant restart at "Starting Windows"

I just finished my first computer build. It was working fine, so I decided to take my graphics card and install it since everything else seemed good.

I install it and the most recent drivers from ATI. When I reboot, it gets to "Starting Windows" and then restarts. Safe mode still works. In my BIOS it says the GPU voltage is 0.000, however the fan on the card is spinning.

I've tried everything I could find on the web to no avail.

Does anyone know what this mixture of symptoms could be caused by?

Thanks for your help.

is the PCIe Connector from the PSU plugged in to the GPU?

It might help if you properly fill in your system specs.

Ok, updated my system spec information.

Yes the GPU is plugged in, fan is spinning fine. Works fine in another computer. In the new build however, the PSU doesn't have any 6 pin connectors, just 6+2. Would that make a difference?

Okay, give this a shot;
Do a full back up and create a restore point.
Download, install, and run Driver Sweeper to remove the GPU drivers.
Download and save to the desktop the newest drivers for your GPU.
Power down the PC.
Change video signal cable to onboard video.
boot from the onboard video.
in the device manager, if the GPU is listed uninstall it and disable the onboard video.
turn the computer off.
change the video cable from the onboard to the GPU.
reboot into the bios.
disable the onboard video and set it to detect PCIe first.
save and exit the bios.
when windows finishes booting, disable your antivirus.
install your drivers for the card
reboot the computer.

NOTE: Before changing the video cable to onboard video, you may need to change your BIOS settings to use onboard video, as well. It depends on how your motherboard works and how the BIOS is configured.

And that, thanks writhziden.

Yes, I've been disabling and re-enabling the onboard from there. When it's the onboard everything is perfect. Switching to the PCI causes the problem. Would it be caused by the order in which I'm doing the install? When I first put in the video card, it loaded Windows to a low-res screen with the default background and the cursor in the middle, seemed to be installing an update for the driver. Then the restarting would happen and it wouldn't get past "Starting Windows."

Okay, did you follow the steps that were laid out? This will ensure a clean start for troubleshooting purposes.

Sorry didn't see that. I'll give it a try tonight!

Thanks so much for your help!

Okay, let us know how it goes.