Lost monitor signal, limited resolution across different cards

I recently got a new Gateway FX542X from a nice deal at Newegg, which came with a factory overclocked Geforce 9800GT. From the beginning there were problems - the monitor would lose signal after the green start-up loading bar, which would be temporarily fixed by unplugging the monitor from the computer and plugging it back in. Then, the card would only allow me to go up to 1024 by 768, on my monitor which supported up to 1680 by 1050 with my old computer, which had a Geforce 8600GTS.

After trying numerous other things to try to get the card to work normally, I decided to try the new computer with the old 8600GTS to see if that would work normally. Sure enough, with the old card, the new computer went up to 1680 by 1050 and did not have the lost signal problem.

After restarting the computer with the old 8600GTS, though, I'm back to having the same problems (as in the first paragraph), meaning that it's probably not an issue with the card itself.

Has anyone else had these issues across multiple video cards? If so, any fixes?

Thanks.

Thanks, but I already tried installing the newest drivers... I should have mentioned that.

+1 ^

Sounds like your monitor is giving out...

I have tried the other DVI output, and as of today I have tried a different monitor; same problems.