Has anyone had any issues with Dell e4300, 4310 or e6400's freezing when they should be hibernating

Has anyone had any issues with Dell e4300, 4310 or e6400's freezing when they should be hibernating. We have have some users complaining that the screen just freezes with the last thing they had up, or the screen goes blank and they can not start up the machines with out forcing the machiens to shut down. we are running windows 7 64bit  in our organisation, and the issue seems to be only effecting these machines. There are no error logs in event viewer except to say the machine was shut down incorrectly.

any help would be usefull.