GF FX5200 Graphics Card Problem. Help?

I have the Dell 4600 series with the GeForce FX5200 and i had to recently reformat it due to a bad virus. Then I installed the driver for the graphics card. Now when i restart it, my computers screen goes to a low resolution and turns the quality to 4-bit and will not let me change it.I have a Windows XP 32-bit. Please help :C