When you install a graphics card, you usually have to disable the integrated graphics in the mobo or CPU. If you didn't do that, it's probably your problem.
Good luck.
Recently I put a desktop tower together. I have a bit of experience adding hardware, downloading software, and some other basic things with a computer. This is my first time doing it from scratch.
So my problem is my monitor is noticing the graphics card but there is nothing being projected. I have taken all of the excess hardware out, and have done it piece by piece, still nothing on the monitor. I took the graphics card and put it in my 5 year old computer and it starts up without a problem. Now I've ran out of ideas.
Motherboard: GIGABYTE GA-990FXA-UD3
Graphics Card: GIGABYTE GV-R645D3-512I
Processor: Athlon II X4 640
Ram(DDR3-1866): G.SKILL F3-1866C10D-16GAB
Hard Drive: Seagate STBD2000101
Power Source: Raidmax RX-500AF
Side notes - I haven't done anything with the BIOS yet because the computer does not have an on-board video.

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