you remove the back plastic mount of the stock heatsink, and screw the mount that comes with the xp-90. It is really easy, It only takes 2 screws. The xp-90 should only take you 5-10 minutes to install once you read the directions and know what to do. It really is a good heatsnk. Mt CPU stays nice and chilly overclocked to 2.64.
PVD