Monitor Color Only Good in Safe Mode

I have just installed an additional drive that will be the primary drive. The monitor color quality in the display settings is at the lowest of 4 bit using the new hard drive. I own a Dell 20″ flat panel and the resolution for this monitor on the new drive is 800 x 600 pixels when I connect the new drive. I have downloaded and installed the latest driver from Dell but this does not make a difference.

I have used the troubleshooter but still no difference. I have rebooted in safe mode and the color and display settings are fine. The color and display settings are fine on the old drive.

Can someone please advise?