Yeah I had this problem too when I got a CTX LCD monitor... I had to go download a patch... I believe I got it from Nvidia.com website.
 
I'd go look and see if you can't get it.

I know you can do it manually by editing the .inf file of the display driver and adding in the refresh rate you want next to the entry of the graphics adapter type you have.

Try looking here, it's a guide to manually altering your refresh rate:
 
http://www.speedy3d.com/articles/nvidia_rrfix/index.shtml

Why not just download NVrefresh?
 
 
It works fine on the 27.70 drivers, at least it has for me on 4 different computers, with 3 different types of Nvidia card(TNT2, GF2MX, 2x GF3)

Here's the link: http://www.fileplanet.com/dl/dl.asp?/planetquake/ztn/nvreffix-setup.exe

MultiRes is said to work.

yes but Multires 1.has to be running in background 2.doe's not work with all games. Powerstrip on the otherhand does,but is also running in background.

I use Win2k and I've just upgraded to a shinny new GeForce 4400ti and I can no longer user Powerstrip 2.75 to set my fresh rates as I did before when I had a GeForce DDR. I've upgraded the drivers the the new altered ones which are compatible with nvrefresh but it still doesn't seem to work. I managed to use dxdiag to set dx stuff to 85hz but this does not work in opengl games. I've tried using the latest powerstrip 3.15 but it is not the same as the 2.XX ones where you can easily set the rate for each res (a major backwards step!)
 
What do I need to do?
 
Running at 60hz is a mojor pain (especially on the eyes!) so god knows why Nvidia can't make it easy to set it properly.
 
I need Help!
 
Some Call Me Tim

As far as I know the 23.11 drivers are the only one's that work most often with W2k/XP and OpenGL. The rest have to be "tweaked". Apparently, Microsoft DirectX controls the drivers. When W2K/XP shells out to OpenGL, DirectDraw, which retains control, has to be bypassed by a fix in the video drivers themselves.
 
The second problem is that some OpenGL games are defaulted for 60Hz. So, these too have to be readjusted.
 
Many solutions are given above (Powerstrip,RivaTuner,NvRefresh) that work for some and not for others. Try this http://www.3dcht4u.de/3dc/11gwe7/w2k-nvidia-refresh-rate-fix.zip it too has worked for some and not others. However with all these "tweaks" setting one thing one place means resetting in a variety of other places elsewhere.

Try this program. Worked for me
 
http://www.pagehosting.co.uk/rl/