Possible Duplicate:
What should I do when Ubuntu freezes?
I installed ubuntu on my new computer (no other OS) , and it crashes suddenly all the time , There is no program that i specifically use when ubuntu crashes . When it occurs , I can't move the mouse or do anything , it stops disabling any move but doesn't shut down the computer or show an alert or something like that .
I use Ubuntu 12.04 64 Bit . My computer : HP Pro , intel i7 processor , ram 8go , nvidia gt520 2Go , 20" HP 2011x LED screen .
Excuse me if I made mistakes , english is my third language .
Please Help .