Poweredge R320 processor compatibility

Our 'old' PER320 (rackmount) is "severely over-taxed" since it still has the 'stock' E5-2407 2.2GHz quad-core XEON processor installed.  As it stands right now, the owners are a tad reluctant to replace this server, so I need to 'upgrade' this bad boy as much as is possible (I know, I know... with ALL possible upgrades, this will cost nearly as much as an entirely new server - but I'm just the 'nerd' and it isn't always necessary to listen to what WE recommend...).   So I've been on the hunt for an "affordable" processor upgrade .. (at least for now until my 'reasoning' meets more receptive ears).  So - I know the PER320 normally supports E5-2400 series as this mainboard supports these 'out-of-the-box', and I've looked at E5-2440's (hexa-core) and E5-2470's (octal-core) and the prices aren't actually as bad as I might have originally estimated ($$$$), but I just stumbled across an E5-2470 V2 (which is a deca-core - nice! 10 cores and hyper-threading too..?) which SEEMS to have very similar specs as the E5-2470, and is being offered locally for what I think is a remarkably cheap cost (it's good to have friends in the 'refurb' and 'lease-return' business, no doubt..).  So, according to the supplier, this "chip" is "tested and verified" fully operational, having been removed from a 'damaged' rackmount server just this past week.  But is there something about this chip I'm not aware of as it might pertain to the PER320?  Or maybe something I'm just 'ignoring' in my drive to put some 'spunk' in this server..?  Or maybe I am simply dreaming that this might actually function in the R320..(?) Gotta do something... this server is just TOO slow and cranky...

BTW: the RAM has been upgraded in the PER320 to 32 GB, and all the four of the hard disks have recently been replaced with larger, faster disks since they'd 'overrun' the previous storage space in just two years.  (but ".... buy a NEW server..?  Nah...  Didn't we just buy THIS one..?")