Why does my computer screen keep giving off a yellow tint?

Check to make sure the pins on both ends of the cable that attaches the monitor to your computer are not bent, and make sure each end is securly fastened in. You can additionally go into your monitor settings, usually a push button physically on the monitor somewhere, and run the DeGauss option. This is especially helpful with LCD montiors. You did not say weather it is an LCD or CRT screen. If the cable is secure, you degaussed and it is a CRT monitor, here is a last resprt. Give the montior a solid BAP on the side. I know people will disagree with this, but works womders for me most times. Of course it means something is loose, but it does work. Do NOT do this if you have any type of Flat Panel monitor, however.