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Due to a bug, certain Intel chipsets were added to blacklist of Compiz. Compiz is intentionally disabled on these machines, and the effects & animations stopped working. This lead to a confused state for people who updated to Jaunty just to see their effects gone when they worked flawless in Intrepid and previous versions (This includes me too). After I’ve installed Jaunty and tried to enable the Desktop RightClick>Change Desktop Background>Visual effects, it throwed up “Desktop effects cannot be enabled”.

Googling immediately after the Jaunty release didn’t return any results, but  googling now we can find a number of results for solving this. The two workarounds I found are:

1. Reverting to 8.10’s Intel Drivers (How to: Link)
2. Making Compiz skip the check (How to: Link)

Unfortunate for me, both of them didn’t work. I’ve searched deeper into the launchpad and found the solution in the bug 363821 report page. Here’s the work around:

1. Open the file /usr/bin/compiz with root permissions in a text editor
2. Go to the section “# blacklist based on the pci ids”
3. Add a # before the PCI ID of your graphics card (Commenting the line excludies it from processing)
4. Save, Close, Restart
5. Desktop RightClick>Change Desktop Background>Visual effects and choose your favourite mode.

How to find PCI ID of your card? Use the following command:

$lspci -nn | grep VGA

This usually gives a output like the following:

00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller [8086:2a02] (rev 03)

8086:2a02 is the PCI ID of this Intel Card. In the /usr/bin/compiz file, You’ll be changing as follows:

Original -

T=”$T 8086:2a02 ” # Intel GM965

Modified -

#T=”$T 8086:2a02 ” # Intel GM965

Warning: Be careful about removing your card from the blacklist. It may lead to crashes of X. If you are experiencing such problems, login in safe mode and add the comment back so that Compiz gets disabled.

My card is the one listed above, GM965/GL960. It works absolutely fine with compiz with no crashes.

Update: After three weeks of usage without any crashes, I’m beginning to see some of the glitches due to which the card was blacklisted. X is getting freezed, but I can still here the songs running in the background or the notifications of applications running. Just the video gets freezed. Am reverting to Intrepid’s Intel 2.4 drivers (See workaround 1 in the above post). Hope Ubuntu developers will fix the problem soon…