Possible DirectX problem?

When running some games that I used to be able to run, I no longer can. it began when I got Champions Online Beta, and installed it. Basically, the program would start, patch would download, but when I would actually click PLAY from the splash screen, nothing happened.

Recently, I reinstalled Neverwinter Nights II. The same thing happens with that. CD goes in, splash screen comes up, click PLAY and... nothing.

Now, the strange thing with the Champions Online, I had it installed to my bigger, 500 drive. I uninstalled it and installed it to my smaller fast drive with my OS on it, and it ran fine. That wasn't the case with Neverwinter Nights II, it wouldn't run on either hard-drive.

Fallout 3. I've played it, beat it. Havn't touched it since. Installing a new 9800GT, I started Fallout 3 to see how it ran. No splash, nothing.


I had an 8800 Ultra card [Ran hot as hell], and recently bought a 9800GT.
TF2, Civ 4, Sins of a solar empire, all those games run just fine on my PC. Any idea why I'm having errors like this?