And in case you are wondering I lost the information that came with my monitor and I don't know where to find the info on the web.
Er, second hit on google: http://sirexonline.co.uk/product_inf...roducts_id=220
If yast/sax doesn't work, then edit /etc/X11/xorg.conf manually and enter the correct parameters, which you can find on that link (the maximum values are the important ones i.e. 80K horiz, 75Hz vert, the lower bounds are less important, 35 and 50 respectively are common values, X will probe the correct values anyway once you get it going, and you can grab them from the log file).
edit: OK, that might have been a bit vague for a noob, here's my monitor section as an example:
ModelName "Relisys TL795"
Just diddle with your HorizSync and VertRefresh, and ensure that you have 1280x1024 as your default res in the Screen section, e.g.:
Viewport 0 0
Modes "1280x1024" "1024x768" "800x600" "640x480"
and that should do it.