Buy the fastest non-extreme consumer intel processor, What I typically do is buying a used company workstation from eBay (they are often sold by the tens). Thi

Buy the fastest non-extreme consumer intel processor, What I typically do is buying a used company workstation from eBay (they are often sold by the tens). This gets you a nice robust 4/8 core Xeon machine with a lot of CPU cache and 16 or 32 GB memory (somtimes ECC) for ~300-400 Euro. Add an SSD you are done. They typically come with a Windows Pro license as well if you need that. Edit: since the hardware is typically 2-3 years old and certified for Red Hat Enterprise Linux, everything typically works out of the box on Linux or FreeBSD.