Recently I have installed Cassandra on my two computers (both me and my wife love it!!!) - a stationary (athlon64 3200+, nvidia 6600 512 mb) and on a laptop (HP pavilion zv 5206, Celeron 2800, ATI 9000 IGP with shared memory up to 128mb). On both machines I have the same issue - the screen just never comes back only stays black. To put the system to suspend or hibernate works fine, the waking is the problem. I've been looking on different forums and found nothing, no solution, though a lot of people seem to have the same issue.
An additional problem with the laptop is that I cannot even install ATI drivers through Envy or Restricted Drivers Manager. Envy returns an error saying the driver does not support my hardware and RDM says I don't need any driver. I'm not saying I do need one, I only tried to install it hoping the suspend thing would work then. Well, it doesn't.
I hope someone has a solution or if not that the developers will solve it eventually.