First of all hi Guys

,
I have a serious problem in my PC

. A few days ago I have installed "GTA San Andreas" While I was playing, I saw triangle things on the screen. (I mean in the game). This thing happened again and again. So uninstalled it. And started to play "PES 2012". While I was playing, I saw these damn triangle things again in grandstands. Today I installed "Operation Flashpoint Red River". And these things happened again. I need help guys. I uploaded a picture and my system.