When you click 'apply' the screen should adjust, and then a small confirmation dialog should appear with yes/no answer buttons, defaulted to 'no'. Unless you press 'yes', your settings will not stick.

Yes, I do all of that but immediately the screen flickers and reverts back to the original setting. I'm beginning to think that maybe it is a rare bug with nvidia as I've searched on-line and a few people have reported having this problem in the nvidia forums. I've even completely uninstalled and then reinstalled the drivers with a clean install to no avail :(

I had hoped that it was a simple thing I had overlooked especially knowing how temperamental Win 7 can be! :)

It may be a bug, but not necessarily with the drivers; it is possible that the correct keypress is not being registered. Try rebooting *before* you change settings. It may or may not work, but it's worth a shot. NB: you *must* use the mouse; using [Enter] will default to 'no'.

Ok, I've tried rebooting and then changing the settings but the same thing happens. I click (with the mouse) Apply and then Yes, save the settings. The screen then flashes and reverts to the original settings. Grr! I have absolutely no idea what my computer is playing at!

Anyway, thank you for the help though :)

Maybe it has to do with your settings files? The nVidia settings are stored in C:\ProgramData\NVIDIA Corporation\Drs\, so you could try renaming the Drs folder and creating a new one, so that new settings are created -- I know you said you did a clean install, and these should have been overwritten, but again it's worth a shot.

I gave that a go but still no luck. I'm going to officially admit defeat but many thanks for your help +1

OK, I've cracked the problem and thought I'd post in case anyone else has the problems that I had regarding the Nvidia Control Panel not accepting a change to the 'Aspect Ratio' settings. I worked out that my monitor settings were overriding all other settings so I changed the aspect from 'Full' to 'Aspect' within the monitor settings and voilà! no more stretched games and one very happy gamer :)

Great. Thanks for reporting back on the solution. :)

Thanks Pajama for posting your solution. I wish it had worked for me, but my HP monitor doesn't let me change image scaling (aspect, or whatever you wanna call it) as the option is greyed out. Damn...
EDIT: Found a solution on here, thanks to user phaolo.
Copying and pasting here:
This topic explains how to make 640*480 and similar resolutions not stretch horizontally on a wide screen. Buggy NVIDIA Control Panel of the latest drivers resets scaling to "Full-screen" whenever you set it to "Aspect ratio", at least for me. Below is a fix that requires using RegEdit, so you may want to create a restore point before doing it to feel safer.
- Set "Perform scaling on" to "GPU" in NVIDIA Control Panel.
- Open RegEdit with admin rights (use search in Start menu, then Ctrl+Shift+press on it).
- Navigate to "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers\Configuration\(long string of symbols that describes your device, normally the only folder out there)\00\00".
- Change "Scaling" to "4".
Done! No restart required.
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