The Intel Core i5-9600K is a little over a year old at this point, but it's still one of the best gaming CPUs you can buy, especially since it has continued to fall in price over the past few months. Now you can grab one from Newegg's eBay store for just $194.99, a savings of $85 from the original price.
This CPU is part of the Coffee Lake family, with 6 cores/6 threads (no Hyper-Threading), a base clock of 3.6GHz, a boost clock of 4.6GHz, and Intel UHD Graphics 630 built-in. It can support up to 128GB of 2666MHz DDR RAM on two channels, and up to 16 PCIe lanes.
Of course, you'll need to pair it with a FCLGA1151-socket motherboard. Check out our best gaming motherboards roundup for some recommendations, if you don't already have a compatible board. Since this is a K-series part, you'll also need a cooler, so check our best CPU coolers for options.