Really very good, installs in less than fifteen minutes, an incredible silence and since my computer regained his energy over crash, opening pages super fast startup even suited for a PC Sempron processor at (AMD) over the temperature of my computer down to almost 10 degrees view that the hard disk no longer force the opening and the ventilos have found all their vitalities. This diet so two ventilos one rear overlooking outside the PC, and one that is below if you install the right way the so-called power, not as I've read on the fan or a comment was rediscovered glued to the sheet from the top of the PC when you install requires that the on / off button is found on the left when you looked at the back of the PC and the main power outlet it is below this on / off button.