hi,
I have googled for days but found most results are old and said that this issue is supposed to be fixed.
And I couldn't found how to fix this.
The gnome-shell is laggy when changing between workspaces. This also occurs when openning a new tab in google chrome.
The overall graphic seems twitchy too.
Graphic card:
Radeon HD6790 x2
(Note that no matter the CrossFireX enabled or not, the issue persists)
Debian Version:
7.1