I just installed Ubuntu 12.04 (32bit) in my PC using wubi installer and have an issue regarding the screen resolution. I have Intel integrated gfx chip and my monitor supports resolution larger than 1024x768, i.e. 1152x864 (on the same PC in win7 I've been using 1152x864). I don't have any external graphics card.Now, I'm stuck with 1024x768 resolution and seems I can't change it.

Running xrandr gets:
Screen 0: minimum 320 x 200, current 1024 x 768, maximum 8192 x 8192
VGA1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768       60.0* 
   800x600        60.3     56.2  
   848x480        60.0  
   640x480        59.9
Any help in this regard would be appreciated