Screen resolution on Linux (Ubuntu)

I recently installed Ubuntu on the entire hard drive because I do not want Windows. But now that installed my display resolution is really not optimal. Resolution in the menu, I have no choice manager and driver, there are no drivers. (otherwise, everything else seems to work well).

As for my laptop, a Dell Inspiron 2600. I did a "test equipment" where I was notified that the display resolution was not good, but they do nothing more.

That is what I have in typing the command lspci:

00:00.0 Host bridge: Intel Corporation 82830 830 Chipset Host Bridge (rev 04)
00:02.0 VGA compatible controller: Intel Corporation 82830 CGC [Chipset Graphics Controller] (rev 04)
00:02.1 Display controller: Intel Corporation 82830 CGC [Chipset Graphics Controller]
00:1 d.0 USB Controller: Intel Corporation 82801CA/CAM USB Controller # 1 (rev 02)
00:1 d.1 USB Controller: Intel Corporation 82801CA/CAM USB Controller # 2 (rev 02)
0:01 E.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev 42)
0:01 f.0 ISA bridge: Intel Corporation 82801CAM ISA Bridge (LPC) (rev 02)
0:01 f.1 IDE interface: Intel Corporation 82801CAM IDE U100 Controller (rev 02)
0:01 f.3 SMBus: Intel Corporation 82801CA/CAM SMBus Controller (rev 02)
0:01 F.5 Multimedia audio controller: Intel Corporation 82801CA/CAM AC'97 Audio Controller (rev 02)
0:01 F.6 Modem: Intel Corporation 82801CA/CAM AC'97 Modem Controller (rev 02)
02:01.0 Ethernet controller: 3Com Corporation 3c905C-TX/TX-M [Tornado] (rev 78)
02:04.0 CardBus bridge: O2 Micro, Inc.. OZ601/6912/711E0 CardBus / SmartCardBus Controller

Note that I have no choice of resolutions in the board resolution. There is only one: I would like 640x480 and the screen is in 1024x768!

Surely a driver not loaded, and you turn on the basic via compatibility mode. You are right updates? What version of ubuntu? If not, is what you could post your xorg.conf? You should not normally have problems, especially with more young stuff, I just think that your drivers are not updated too.

Yes I have automatic updates. The version of ubuntu is as follows:
8.10 (intrepid)
Linux kernel 2.6.27-11-generic
GNOME 2.24.1

As for the xorg.conf file:

Section "Device"
Identifier "Configured Video Device"
Driver "vesa"
Option "UseFBDev" "true"
EndSection

Section "Monitor"
Identifier "Configured Monitor"
EndSection

Section "Screen"
Identifier "Default Screen"
Monitor "Configured Monitor"
Device "Configured Video Device"
EndSection

No ideas? I guess that I have to change things in the Screen section, but I do not know how ...

I forgot to say that I have nothing in my drivers manager. No driver appears.

There is no need to install drivers for Intel. Adding: Modes "XXY" in the screen with "XXY" the resolution you want. Then made ctrl + alt + Backspace to restart the X server

Rather (if you preserved the wrong driver): change "vesa" with "intel" (I believe, to use the intel drivers to check). 3rd solution: the xorg.conf you aside, your version of xserver no longer required (for example: sudo mv / etc/X11/xorg.conf / etx/X11/xorg.conf_backup and ctrl-alt-backspace)