I recently got an older HP Proliant Server (10 years old) for my home testlab and would like to upgrade the hardware with an additional Intel X5675 (so that I have two CPUs in total), but the manual said I need a matching pair for CPUs which lead me to this question.
As I normally do not need to deal with server hardware, I´m not totally sure what "matching pair of CPU" mean? The internet isn´t really clear about that as they said:
I can find some "matching pair of CPU" kits on various shops. However I do not need a kit, I need only a 2nd CPU which "match" the first one. I also think that companies normally order one a 2nd CPU for an already existing 1st one and do not dump that. Additional the CPU/processor microcode seamed to be part from the OS/BIOS (see here) and isn´t part from the CPU/processor. Means if the BIOS / OS from the server is up to date both CPUs/processors would then use the same microcode. For the X5675 there seamed to be also only one B1 stepping (as seen here).
So some general guide how to find a matching pair of CPU (or in my case a matching 2nd CPU) would be really helpful (and maybe not only for me).