Yes, the first generation board does have limited support for non-130w 5600 series Westmere CPUs. The information I provided previously was not accurate. There is a processor information update in the documentation section of the R710 support page. It has more detailed information. [URL]
Greetings!   Recently bought PE R710 and it appears to be Gen.1 i believe: DRAC says System Revision is "I" and labels on the motherboard suggest the motherboard is 0N047H however it doesnt match the label on the side of the machine which is 0H241F. I want to upgrade the CPUs for the purpose of my needs to the fastest, highest core count CPUs I can put in it. As far as I understant, considering its Gen.1 and can't host 130W TDP cpus, I can go for X5675. Is that correct?   Current BIOS version is 6.4.0 - can I use it or upgrade is needed to host X5675 - I rather not upgrade the BIOS because I dont want Specter/Meltdown security mitigations -> currently performance is more important than security.     Side question: in Power Monitoring in DRAC (as well as on LCD) power reading says 245W in IDLE and DROPS when system gets pushed hard which does not make any sense. Measured with external tool it is actually 125W when IDLE. I also upgraded to the latest DRAC FW 2.91 but readings didn't change.
CPU upgrade PE R710