I was dying to find a large air cooler for my 9900K that wouldn't block my RGB lighting. The Thermalright Macho line of coolers were the only ones I could find that provided this. The installation went well, I used the MX-4 instead of the supplied thermal paste and checked the temperature immediately after booting. In a panic, I had to switch off the system immediately because I was only in the bios at the time. After removing the cooler and looking at the contact pad it left on my processor, I saw that there was only a small piece of contact right in the middle. I took a ruler from my tool kit and placed it on the base of the radiator and was amazed that it wasn't even remotely flat. I knew if I was going to run this cooler I would sand it down with sandpaper before it could be used. It took quite a long time because I had to use coarse, then medium, and then very fine sandpaper to get the right finish. It sucks that I had to do this, but when I finished I had an amazing CPU cooler. My CPU is now running at 5GHz for all cores and is around 55 degrees when gaming. even said that its processor's IHS was permanently changed after reviewing several of their different models. currently. It's just awful, although I had to spend a lot of time getting it to work the way it was supposed to work out of the box. Also, I had to delay assembly to purchase the correct sandpaper from the hardware store.