I'm about to build my second workstation and I realized the value of used parts. Are these parts compatible, and are they a good value compared to a new build. I can't find a cpu under 600 dollars that is even 10 cores, so I think buying 2 E5-2690s (v1) is a steal. For my ram, I am going to use ddr3 1333 pc3-10600r from http/m.ebay.com/itm/64GB-16x-4GB-PC3-10600R-DDR3-1333MHz-ECC-Reg-Server-Memory-RAM-/142365938856?hash=item2125abd4a8%3Ag%3AdRkAAOSwa~BYYvNA&_trkparms=pageci%253A212d1e97-7c5c-11e7-a75d-74dbd18056c8%257Cparentrq%253Ac2d13ecf15d0ab64834f64b1ffffda7c%257Ciid%253A6 (btw will there be a performance difference from the 16gb of ddr3 1866 memory I am currently using). I will be using an intel s2600cp2j motherboard from http/m.ebay.com/itm/253073668326?_trksid=p2349526.m2548.l4275&_mwBanner=1. For my cooling I will use two of the cooler master hyper 212 evo coolers. For my case I will be using the planted ethos pro case, and for my gpu, I will be using my r9 390 from my current build. Is this build better than a all new build around $800, and are all the parts compatible? Thank you very much have a good day.