I have been getting annoyed with this lately. I get it everytime I'm on a game it seems. 30 minutes in game or so then freeze then long beep and keeps going until I reboot manually. I never got this with my 4870 x2 so I dunno if it's drivers or one of my 4890. Can't be my SSD's cause I never had this with my 4870 x2 and SSD's in RAID 0 so it must be my 4890. I have uninstalled my 9.5 drivers then ran driver sweeper in safe mode then re installed but still persists.