The Dell Support site shows that the 6650 is support for ESX 3.5 Update 1, but not Update 2.
Why does the 6650 only work under ESX?
Why isn't update 2 supported?
What exactly isn't supported by ESXi on the 6650?
Does this mean ESXi will not intsall/run on the 6650 or that it just doesnt have support from VMware/Dell? I see post in this forum and others where people are asking questions about a ESXi running a Dell 6650, so I assume it installs and runs...
First, it's quite likely that the 6650 actually does run ESX 3.5 updates 2 and/or 3 just fine. It probably just hasn't been completely tested/confirmed, yet.
I'd say something similar is probably true for ESXi, though I'm not quite as certain on that one. ESXi has been trimmed of a lot of the service console, and there may be some hardware drivers missing from it that exist in ESX. Or, the drivers may work fine, and maybe VMware and/or Dell have not gotten around to testing it out and officially certifying it.
This does not necessarily mean that ESXi will not run on the 6650, it just means that, if you have trouble getting it installed or you have problems with it on the 6650 after getting it installed, VMware (and maybe even Dell) will not provide you support for those issues because they have not confirmed that it is functional on that hardware. You can give it a try if you like and report your results back here! You can also check out the "ESX Whitebox" sites that are out there (just Google "esx whitebox") and see if anyone else has had success with the PE6650.