Installation is fairly easy, and makes installation into a case which has a CPU retention hole in the back a breeze. The design has you secure the cooler to the motherboard by attaching the mounting screws, which use spring tension to apply pressure and help prevent over-tightening, placing the cooler onto the motherboard, and securing the screws through the back of the motherboard. This means you can install your motherboard and not worry about being able to reach the ever-increasingly difficult upper left motherboard screw, and then from the back, through the CPU retention hole, secure the cooler to the motherboard. A breeze overall, and I was happy with Cooler Master's mounting design here.
The Test System:
CPU: Intel i5 2300
Motherboard: MSI P67A-GD55
RAM: 2x2GB Patriot Viper Xtreme 1600MHz DDR3
GPU: BFG GTX 275
For idle testing, we booted up the system, allowed the CPU to stabilized at below ~0% usage, and then tested for at least 10 minutes, and we used RealTemp to record the CPU temperatures once the temperatures were stable. The single temperature recorded was the average between the four cores.
For our load tests, we used Prime95 to stress the CPU to 100%, and let it run that way until the temperatures became stable, and then used RealTemp to record the temperatures.
The GeminII S524 did very well in both idle and load testing, doing comparably or slightly better than two, large tower coolers in the idle tests, and besting the Mine 2 cooler in the load tests. These results neglect possible added cooling benefit to other components as well. The Hyper 612 PWM performed fantastically, so a top-flow cooler performing better than other large tower coolers, and still within a reasonable distance to one of the better coolers we have tested says plenty in itself about the GeminII S524's performance. It's more than adequate for aggressive overclocking, and the reduced profile from traditional tower coolers should open up a wide array of applications in cube or HTPC computers. The versatility and "all-over" cooling of a top flow cooler, while still being an OC performer should give the GeminII S524 a little momentum, where momentum has been hard to find for the top-flow cooler market.