I have given this advise on Hacker News before: on eBay 2-3 year old workstations can be had for 300-400 Euro. Typically these are workstations from companies that replace machines every 2 years or so.
These are typically equipped with Xeon CPUs, plenty of memory, sometimes ECC etc. Moreover, since they are usually HP/Dell workstations, they are certified to be compatible with Red Hat Enterprise Linux, so all the hardware is pretty much guaranteed to work.
These are typically equipped with Xeon CPUs, plenty of memory, sometimes ECC etc. Moreover, since they are usually HP/Dell workstations, they are certified to be compatible with Red Hat Enterprise Linux, so all the hardware is pretty much guaranteed to work.
Just to give one random example:
http://www.ebay.de/itm/DELL-Precision-T1650-CPU-Intel-Xeon-E...
Xeon CPU, 32 GB RAM, 500 GB SSD for 425 euro.