Graphics and video

Hi all, a friend gave me a ASUS g73jh-a1...( one stick of ram 2gb, no hdd, and no o/s) so i had to install ram 2x4 hdd wd 1tb os windows 7 all went well now when i go to start it up, it goes to bsod 2 to 3 times then continues to start windows normally then finally boots up... when it is up, there are no issues,,,, any suggestions as to what is causing this lame problem would be greatly appreciated thanks in advance pippo047....