Just got in a Lenovo ThinkServer TS130 1105 (Xeon E3-1225V1) and a (new, sealed, holographed, looks legit) copy of Windows Server 2008 32/64 (standard) to run on it for a pretty lightweight job (currently handled, adequately, by a terrifyingly old Optima P4 running Windows 2000 server - really lightweight, but long-past-due for replacement, without any particular need or excuse for server 2012...) The 64 bit disc sits there and does nothing. The 32 bit disc boots. I haven't spotted any mention of this in the TS130 Manual (I have now combed it, and find no mention of a need to populate in pairs - a preferred order to populate in, yes, but no mention of pairs being required) but I begin to wonder if it's due to the fact that the 4GB RAM suppled with it was a single DIMM, rather than a pair. Better for upgrading, but perhaps requiring an upgrade (or sidegrade) right away to install the x64 version?? Anyone know? I tried the 64-bit DVD on a desktop with an AMD Athlon II X4 635 processor which normally runs Windows7 in 64 bit, and it booted up just fine.