1366x768 Resolution not available

Hello

I am using a new sony vaio laptop : model VPC EB 46 FG, with Intel core i5 processor, 4 GB RAM, 500 GB hard Disk and windows 7 home premium Operating System. It has ATI Mobility Radeon HD 5650 graphics card. Its screen resolution is 1366x768 (high definition), that is functioning perfectly all right in windows 7.

I have created two virtual machines. On one virtual machine, I have installed windows XP professional and MS Office 2003, it is running very nice, screen resolution in virtual windows XP is functioning perfectly all right, that is - 1366x768.

On the second virtual machine I have installed ubuntu 11.04. But in this mode, the biggest screen resolution available is 800x600 only. Other four screen resolutions available in the System > Preferences > Monitors are – 640x480, 680x384, 512x384, 400x300 which are much smaller. I have been examining various web-site, forums, blogs, and tried large number of permutations and combinations, upgrades and installed various solutions but nothing has given the desired screen resolution of 1366x 768. Can anyone suggest the correct solution for getting desired screen resolution of 1366x 768 in Ubuntu mode also.

Kailash Tiwari
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