Comment 212 for bug 121653

ATIs own Wiki has a few words on this in regards to 7.12:

http://wiki.cchtml.com/index.php/Ubuntu_Gutsy_Installation_Guide#Suspend.2FHibernation_work_with_7.12

Apparently, it works since 7.12 now for all but a few (including my own, grumble) chipsets.

quote:
 Suspend/Hibernation work with 7.12

With Gutsy release, there was a big problem using the ATI proprietary drivers. The Suspend/Hibernate function stopped working. The problem was due to the new SLUB allocator incorporated in 2.6.22 / 2.6.23 Kernel.

The problem has been solved in the AMD Catalyst 7.12 driver release. Suspend/hibernate is not working for FireGL 5250. For FireGL 5200, suspend works with the 7.12 fglrx kernel module loaded (which did not work before this release) , but does not work if X is running.

For Thinkpad T60 with ATI X1400, to get the laptop to wake up from suspend, I had to change the following in /etc/default/acpi-support:

SAVE_VBE_STATE=false

POST_VIDEO=false