In short, I am experiencing the old nvidia aspect ratio problem. I'm using a GTX 280 on an LG l206WTY-BF (1680x1050 native) monitor over DVI, and am trying to run some older games which don't support widescreen. None of the scaling option in the nvidia control panel work - I set them, hit apply, the screen flickers and displays the keep settings dialog, but when I confirm the setting flips back to use the monitors internal scaling (which stretches - I need to set the system to either scale with a fixed aspect ratio or not scale at all). I've tried the trick of setting the display to a non native resolution, then setting the scaling mode and it doesn't work.
The really odd thing about this is that I definitely had this working at some point... When I was running the same system under Windows Vista and possibly with the monitor connected through VGA (there was a time when I didn't have a free DVI cable) it was working (I've tried connecting the current setup with VGA and no dice). Even weirder, when I first tried to set the display I chose no scaling, it worked perfectly but the display was smaller than I was happy with once I went to 1280x1024, at which point I tried to set nvidia scaling with fixed aspect ratio, and ran into the problem. From that point on I have been unable to set even no scaling mode, the only one the program will allow me to use is monitor scaling.
Ugh. I found there WAS, unsurprisingly a control for scaling on the monitors control panel (the hardware one), it was just buried in such a way as to be invisible without knowing EXACTLY what to look for (or in my case giving up and messing with random settings) and undocumented in the pitiful manual. Sigh.
On the driver note, I tried installing the drivers supposedly specific to this monitor for the first time in three years in the middle of this, and the only result was that the monitor that had always worked perfectly got its colour management screwed up until I went back to the generic plug and play driver (and to top it off, even on PnP my gpu was able to tell what monitor it is). Yay for crap support.