I've made a few upgrades to my PC, namely the GTX 980 Ti. I got it incredibly cheap from a guy upgrading to a GTX 1080. The reference cooler was noticeably louder than my old GTX 970 with ACX 2.0 cooler so I attached Corsair's HG10 bracket to the 980 Ti and fitted a Hydro series cooler. The HG10's blower-style fan and the H105's SP120L fans were way too loud at idle. I swapped the HG10 fan with the original Nvidia fan and the SP120L's for a pair of Quiet Edition SP120's and I couldn't be happier. Temperatures went from ~87°C under load to under 60°C and I've set a fan curve to always run at low RPM. Now I'm tempted to add an AIO cooler to my CPU to make my PC even quieter. Maybe if I can find a cheap 6700K first.
I never planned on adding water cooling or LED's but now The Crate has both. For aesthetics I've swapped the Cooler Master Hyper 212 EVO for a Phanteks PH-TC14S with a Corsair ML120 Pro LED fan. I also added DEEPCOOL's RGB 350 kit because it was cheap, and my son really gets a kick out of swapping the LED colours. I also purchased a clear case window from MNPCTECH to show it all off. With the addition of the radiator I was left with two unused case fans so I added a DEEPCOOL fan controller just for fun. It's inactive right now. Maybe it'll be of use in the summertime. All in all I'm really happy with the upgrades I've done. Gaming with the new GPU is a treat.