The E5-2696v3 is the OEM version for like dell, HP,etc, and the E5-2699v3 is identical with the E5-2696v3, but the E5-2699v3 is retail version.
So you can use
http://pcpartpicker.com to find your MB and RAM.
1) regular X99 like Asus X99-A you need the non-ecc ddr4 2133mhz.
2) or the server MB, like Asus X99-E WS because you have only one cpu, you need the ECC ddr4 2133mhz RAM.
One more you need to the Full Tower case for the server MB.