screen flicker and occasional crash

every game i suffer this problem at least one time where the game hungs for and the screen flickers an average of 1 min. sometimes it recovers. sometimes its not.

i pretty much did every popular suggestion out there

1. update driver/uninstalling and reinstalling latest drivers, did not work
2. switch to borderless, crash frequency reduces at least once per game but still....
3. do not let geforce control panel take over lol's local application 3d settings. boosts fps but still cannot stop the eventual crash every game

specs: i3-2310m 2.1 Ghz gpu1 intel r hd 3000 gpu2 geforce gt540m 2gb ddr3