So, this evening's gaming didn't get off to a good start ... If anyone could give me some pointers to troubleshoot this I'd really appreciate it ...
Upon starting the PC I noticed that the BIOS screen wasn't stretched widescreen across my monitor, but was instead square with the black borders at each side. Then the monitor complained about no dvi signal right around the time the windows logo should appear (Windows 7). The PC seemed to continue to boot normally, and I tried logging in and watched the disk access light and the machine seemed to log in, but there was no picture.
I restarted and tried safe mode, which worked and gave me a 1024x768 res. I tried a restore point, restarted, and had the same issue. Restarted again, reinstalled the current nVidia drivers from their website, restarted, same issue.
By now I'd tried hooking up my laptop to the monitor, which seemed to work fine. So I went into BIOS and enabled on onboard graphics, and connected the monitor using the motherboard VGA connector. I'm using the computer like that now, and getting the screen's native 2048x1152 resolution, but of course graphics performance is dire.
Tomorrow I'm going to borrow a DVI cable from work just to be sure it's not something dumb like the cable, and I'll try hooking up an iMac to the dvi port to verify the dvi on the display.
With that out the way, I have to suspect something is wrong with the card. It's an nVidia GTX 285 and is I suppose around 3 years old. I was perfectly happy with the performance of it and not really looking to change it out. Is it likely I need a new card?