Hi and welcome to Serverbuilds.
You might want to consider skipping ahead a generation and going with an NK 6.0 build.
You should get a significant bump in performance for a similar or slightly higher price tag. Especially if you are planning on using a fairly exotic (expensive) CPU like the i7-5775C. An 8th or 9th Gen i3 will likely provide better single thread performance and should come pretty close to matching the 5775C in multi threaded workloads and has a much more advanced iGPU for transcoding all on a faster DDR4 platform. You should be able to pick up CPU + Motherboard + 32 GB DDR4 for under $200. Additionally with an NK 6.0 you wouldn’t need the Quadro.