New computer build keeps freezing up?

-I built my first build yesterday and had Windows 7 installed and everything. Once I started to install updates, it would freeze, also making a loud noise on my speakers if it was on. It did it again when I was trying to install some games.



My specs are

AMD Phenom ii X4 965 BE

AMD Radeon HD 6700 series

2x2GB G Skill Ripjaw DDR3 RAM

Asus m4a79xtd evo MBoard



I checked my CPU to make sure it wasn't overheating, 43 degrees Celsius.



My power supply should be enough, 550w Antec PS.



Why does it keep doing this?