An underpowered/unstable power supply unit would also cause that.

--
DaveW



"Jason Gallas" wrote in message
...
I have upgraded my video card from a PNY GeForce FX 5500 to a PNY
GeForce FX 5900. I just took the old card out, put the new one in and
booted up. I then re-installed the 61.77 drivers from Nvidia's
website.

Now my system flashes to black every now and then. I did a google
search and a website suggested completely uninstalling the old driver
in safe mode and then rebooting and installing cleanly. They also
mentioned a utility to uninstall.

Is there such a thing for Nvidia cards, and if not what is the best
procedure for this? Also, could these problems with the screen
flashing black be caused by something else?