NZXT makes one of the best CPU coolers if want to go the all-in-one liquid cooling route, that being the Kraken X62. That will set you back about $140. If you want to save a few bucks and can live with a smaller radiator, NZXT's Kraken X52 is on sale for $99.99.
The Kraken X52 has a 240mm radiator. That's smaller than the 280mm radiator on the Kraken X62, though still expansive enough to do a good job keeping your CPU cool. It all supports all of the major sockets (both AMD and Intel) and sports addressable RGB lighting.
NZXT Kraken X52 | 240mm | RGB | $99.99 (save $50)
This all-in-one liquid cooler sports a 240mm radiator comes with a pair of 120mm fans. It also features RGB lighting and extended tubing, and is backed by a 6-year warranty. Buy at Newegg (Ebay)
I've been using a previous generation Kraken X61 for a few years now on my main rig. One of the things that's nice about the newer gen models is the longer tubing. That comes in handy if you own a big case, depending on where you mount the cooler.
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