Ubuntu: Problem with display

I think my PC might have a graphics driver problem开发者_如何学Python. I am running Ubuntu 11.04 on a Dell Optiplex 380. I am using a Samsung SyncMaster EX2220 monitor. Can anyone help me understand why I cannot get a resolution higher than "1024 x 768 (4:3)" when I look at the "Monitor Preferences" screen (System --> Preferences --> Monitors). I need a high resolution with a "16:9" setting to utilize the widescreen capabilities of the monitor.

I am not able to get a widescreen display setting using this monitor. I suspect it has something to do with my graphics driver. The output from "lspci -v" is posted below. Any help/suggestions will be appreciated.

Output from lspci:

00:02.0 VGA compatible controller: Intel Corporation 4 Series Chipset Integrated Graphics Controller (rev 03) (prog-if 00 [VGA controller])
    Subsystem: Dell Device 0400
    Flags: bus master, fast devsel, latency 0, IRQ 43
    Memory at fe800000 (64-bit, non-prefetchable) [size=4M]
    Memory at d0000000 (64-bit, prefetchable) [size=256M]
    I/O ports at ecd8 [size=8]
    Expansion ROM at <unassigned> [disabled]
    Capabilities: <access denied>
    Kernel driver in use: i915
    Kernel modules: i915

00:02.1 Display controller: Intel Corporation 4 Series Chipset Integrated Graphics Controller (rev 03)
    Subsystem: Dell Device 0400
    Flags: bus master, fast devsel, latency 0
    Memory at fe700000 (64-bit, non-prefetchable) [size=1M]
    Capabilities: <access denied>

Thanks!

Are you by any chance running it inside a virtual machine? Like virtualbox? If yes, you need to install the virtual box additions cd, if not, you need to install the proper drivers for your card. Go to Hardware -> Additional drivers.

I have an update. I fixed the issue, although I am not sure why I had to go through this trouble.

I had to regenerate a new xorg.conf file in /etc/X11 folder by using the command "sudo Xorg -configure" after exiting X. Then, I opened the file and added a line in the "Monitor" section that says

Option      "metamodes" "CRT-0: 1600x1200"

and I restarted the machine. Presto! My widescreen is back with the higher resolution.

Thanks!

Add

xrandr --newmode "1280x1024_59.90" 108.70 1280 1360 1496 1712 1024 1025 1028 1060 -HSync +Vsync
xrandr --addmode VGA1 1280x1024_59.90
xrandr --output VGA1 --mode 1280x1024_59.90

in ~/.xprofile and it works.