Comment 8 for bug 395417

Methinks this is fglrx. I have mildly different results if I update to xorg-driver-fglrx_8.632-0ubuntu1_amd64 using the instructions here: http://www.donotargue.com/page.php?id=1537

In that case after suspend it resumes to a screen that's turned on at least - you can see a mouse cursor - but everything is hanging. You can't even Alt-Ctrl-F1 to get a tty login.

I haven't tried hibernate yet.

Setup is as per OP (with fglrx). And in the interests of full disclosure I have "noapic" kernel option (which fixes other problems such as screen dimming buttons and eject button).