1280x1024 is unavailable.

[HUNTER]

1280x1024 is unavailable.
Max available video mode is 1024x768. 
I requested help on http://kubuntuforums.net/forums/index.php?topic=3083053.0
I tried a lot of modifications of etc/X11/xorg.conf and autoconfigs. But nothing help.

Distro: Kubuntu 7.04, 64-bit, DVD
Video: NVIDIA GeForce 7600 GT
Monitor: Samsung SyncMaster 740 BF (LCD, optimal 1280x1024)
CPU: AMD Athlon 64
Chipset: nForce 570

This video mode work in Windows XP.
I am noob in Linux yet. I will give up soon if this problem remain.
How to solve this? Or say me who I should ask.