I've got what seems to be a common problem of a maximum refresh rate of 60Hz at my TFT's native resolution of 1280x1024. When I drop the resolution then the suggested (and required) 75Hz becomes available from the menu. I'm trying to set this using System --> Preferences --> Screen resolution using Ubuntu's own menus. Obviously this doesn't look great at any less than 1280x1024.

I've edited the xorg.conf file to include the resolutions from the monitors manual. Here's the section of the file:

Section "Monitor"
Identifier "Hanon L-1715"
Option "DPMS"
HorizSync 30-79
VertRefresh 50-75
EndSection

Restarted the x-server and no change in the options. Then I added the modeline generated using gtf:

# 1280x1024 @ 75.00 Hz (GTF) hsync: 80.17 kHz; pclk: 138.54 MHz
Modeline "1280x1024_75.00" 138.54 1280 1368 1504 1728 1024 1025 1028 1069 -HSync +Vsync

Again, restarted x and no change in the menu options or the refresh rate. The monitor is also displaying around 60Hz on it's own menu system.

Then I ran sudo dpkg-reconfigure xserver-xorg - wasn't expecting any big changes here as the same xorg.conf was generated as I already had (without the modeline obviously). Restarted x and no change.

Just in case it makes a difference, I installed the nvidia-glx drivers using synaptic package manager, then re-installed. Again, no change.

I can post the entire contents of the xorg.conf file, and the xorg log if that helps. Something from the log that might help is this:

(II) NV(0): Monitor name:
(--) NV(0): CRTC 0 appears to have a CRT attached
(II) NV(0): Using CRT on CRTC 0
(--) NV(0): VideoRAM: 131072 kBytes
(==) NV(0): Using gamma correction (1.0, 1.0, 1.0)
(WW) NV(0): config file hsync range 30-79kHz not within DDC hsync ranges.
(WW) NV(0): config file vrefresh range 50-75Hz not within DDC vrefresh ranges.
(II) NV(0): Hanon L-1715: Using hsync range of 30.00-79.00 kHz
(II) NV(0): Hanon L-1715: Using vrefresh range of 50.00-75.00 Hz
(II) NV(0): Clock range: 12.00 to 400.00 MHz
(II) NV(0): Not using default mode "640x350" (vrefresh out of range)

The first part gives a few clues. I know that this monitor is capable of the resolutions/refresh rates I need as they are stated in the manual and I've been using the monitor in Windows at 1200x1024@75Hz. The desktop manager I'm using is Gnome and OS is Ubuntu 5.10.

Any help please?

Just in case anyone with the same monitor comes accross this post I've fixed the problem. Although the manufacurers website posts:

Horiz 30-79kHz
Vert 50-75Hz

x needed a bit of a nudge

Horiz 30-80kHz
Vert 50-75Hz

Now 60 and 75Hz are available at 1280x1024.