Why does my screen go gray?

Question

I just installed Ubuntu 11.04 on my laptop. However, very often things get VERY slow and windows start blinking with gray color. The system is then almost unresponsive... This goes on and off in about 5 minutes interval. When I run the top command it looks like the Xorg command is using most of the CPU when things get crazy.

I am using HP Compaq 6720s..

lspci | grep VGA

returns

00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (primary) (rev 0c)

Come more specs of 6720s:

Processor: Intel Core 2 Duo Processor T5470 1.60GHz , 2MB L2 cache,

800MHz FSB OS: Microsoft Windows Vista Home Basic Hard Drive: 120GB

SATA (5400RPM), HP DriveGuard Screen: 15.4" WXGA BrightView Widescreen

(1280 x 800) Graphics: Intel Graphics Media Accelerator X3100 RAM: 1 x

1024MB DDR2

Some other information:

00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 0c)

00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (primary) (rev 0c)

00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (secondary) (rev 0c)

00:19.0 Ethernet controller: Intel Corporation 82562GT 10/100 Network Connection (rev 03)

00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 (rev 03)

00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 03)

00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03)

00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 03)

00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 03)

00:1c.4 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 5 (rev 03)

00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 03)

00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 03)

00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 03)

00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03)

00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3)

00:1f.0 ISA bridge: Intel Corporation 82801HEM (ICH8M) LPC Interface Controller (rev 03)

00:1f.1 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) IDE Controller (rev 03)

00:1f.2 SATA controller: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) SATA AHCI Controller (rev 03)

10:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG [Golan] Network Connection (rev 02)

Answer 1

Your system is more than capable of running ubuntu with all the 3d stuff. I have the same graphic card with an old celeron processor and less memory and everything works. I'd suggest you install the drivers for your card:

sudo aptitude reinstall xserver-xorg-video-intel

Also, install driconf and mesa-utils and see if you have hardware 3d acceleration:

glxinfo | grep direct 

should output "Yes" unles your card is not being detected

driconf

will help you tonfigure your graphics.