Does the screen lock with the image still there, or go blank? Screen locks sounds like a driver issue, screen goes blank sounds like a power or hardware issue.
Immediately after a crash...
On bootup, Windows Key, type "event", hit Enter.
Hit the > next to Windows Logs, click System.
If it's a driver issue, you should see an Error with a timestamp before your boot time. Any errors after the boot time are representative of not having a clean shutdown.
Copy and post the information under the General tab of the Error, if any.
Immediately after a crash...
On bootup, Windows Key, type "event", hit Enter.
Hit the > next to Windows Logs, click System.
If it's a driver issue, you should see an Error with a timestamp before your boot time. Any errors after the boot time are representative of not having a clean shutdown.
Copy and post the information under the General tab of the Error, if any.