My computer restarts.....

when i start my computer, if i don't start a game emediatly, it will restart when i try to run a game again. when it restarts i get a litle system mesage saying that my computer has recovered from a serious error and it wants to send a mesage to windows(send-dont send). in details of that mesage i see 2 files with .dmp ending
(C:\Docume~1\PC\Loocals~1\Temp\Werf54f.dir00\mini 082609-02.dmp) or something like that.

P.S.:i don't get BLUE SCREEN just a windows message after restart!