Welcome to the fleet
cgh123.

I'm not a computer expert by any stretch of the imagination, but I have a few ideas that might help.
First, when you installed your new graphics card, did you remember to switch your screen cable over (
plug it in) to your new graphics card, or is it still plugged into the original port?
Also, you must go into your System BIOS in order to switch your graphics from the PC to the new card. You should have a User Manual, either a hard copy or somewhere on your hard drive, maybe in the "
Help" files that explain how to access your system BIOS.
Again, I'm no expert, but your power supply seems a little on the lite side. I would've installed no less than a 650 watt supply.
One more thing: You say you have the latest BIOS. Does that mean you updated it yourself? If you did, did you wait for the BIOS to fully complete the update process before you rebooted? You may have a bad or incompatible BIOS. I would try reverting back to the original BIOS, or updating it again and wait for it to complete before you reboot your PC.