I do a bit of processing on my workstation at work (for 3D VFX/animation/comp) which is a dual ten-core Xeon (E5-2650v3) - so with HT that shows as 40 cores, 64GB ram, win 10.
I use PixInsight
*1, DSS, RegiStax, Autostakkert!, Startools, Photoshop, etc.
Obviously it's very fast for software that uses multithreading efficiently
Personally if I was building an astro processing box, with my own money
, I would just go with a current I7 over an older dual Xeon box. I think you'll probably get similar performance with a current I7 and a dual 8 core Xeon (just a guess - depends on which Xeon and age of course) for a similar price and in that case I'd always go with the more recent technology
*2.
I should also note that I do the majority of my processing on my lappy (2013 XPS15, I7, 16GB) and I've never had anything that I could do on my workstation that I couldn't do on my lappy.
*1 when I first got this workstation I was still running Linux (CentOS) and PixInsight would only use all the cores from one Physical processor - so it would report 20 cores whereas on the same box on Windows it reports 40 cores... weird...
*2 we had an older Xeon that we had to retire recently because it didn't have SSE2 and the renderer we use had an update that required it - took me ages to work out why it wasn't working on just that box!