Buying a refurbished server is an environmentally friendly and cost efficient way of acquiring a server for your home lab. After receiving mine I performed some generic diagnostics with tools like Memtest86, but in my case, the HP Smart Start CD includes the the HP Insight Diagnostics for ProLiant servers.
To get it, navigate to the product page, enter the firmware and drivers sections, search for “Smart Start”, download the x64 ISO and create a bootable pen drive. Boot the server with the new pen drive.
The diagnostics will test and stress all the sensors, fans, chipset, RAM, PSU and CPUs. Its also possible to consult the number of hours the power supplies were in use.
I was happy with the results, and even found out that the PSU in my server where used less than 2 years.