The Xeon 5000 series, especially from the 5100 series up does. I've run 64 bit VM's under the Workstation product on a pair of E5160's as well as (now) the E5345 Xeon's. I have an ESXi host running a pair of E5405 Xeons with a mixture of 32 and 64 bit VM's...
Since you're talking about the X series, not the E series I've used, I did a little checking...
X 5355:
E 5345:
Both list the 64 bit instruction set in their spec's in the exact same fashion. So, I'd say you'd be good to go with 64 bit VM's.
IF so, then it looks like the second one could work (although I suspect it will have issues if it works at all)... The first one is a definiative NO...
I would say that except for the Xeon's that specifically call out being 64 bit processors in their names, such as these: ( ).
The generation that started with the 3000/5000/7000 designation should be your miniumum processor to look at. I would go one step more and say that don't look at anything below a dual core 5100 series processor. IF you can go with a 5300 or 5400 series, grab it. I know, from experience the 5500 series kick some serious ass in performance. The only hold up there is they use a different socket connection compared with the older 5000 series. When it comes time for me to redesign/build my home lab, I'll be going with either the 5500 (5520 being the minimum) or 5600 series Xeon processors. Hopefully, that will be within six to twelve months...
