I purchased a refurbished gateway computer from tigerdirect.com around a year ago. When I first turned it on my computer it had a bluish tint and I had to send in my nvidia graphics card and it took about a month but I eventually got a new one. I haven't had any problems with it other than that up until recently because I never put the graphics card in. however around 2-3 weeks ago I decided to put it in and ever since then it will boot up but only ever so often. When it does not boot up it does one of three things; it will bring up a screen that says gateway and intel, it goes to a black screen but the moniter still gets a signal because the light stays green, or it it brings up a screen that says some copyright info. Also when it boots up it doesn't make a lot of noise like it did before I put the video card in.

Just use the one that works

Regarding with your problem make sure that the driver of your video card are installed, if you have a video card, your monitor cable are attach in your new video card installed, and install also the video card driver.
If your video card driver is not installed it will affect to the settings of your computer.