Updated 4/20/2016 The under $800 home lab is now under $700! Because I am a geek, and my needs change, and this is what I like to do I often check out new hardware, cost features etc. One of the things I wish I did on my 8-core lab was go for a smaller form factor case. Pricing, as always is subject to change. I actually prefer to buy most of my hardware on Amazon because I seem to have an easier time returning items that are defective but I’ll link to NewEgg. You may be able to find a part or two for a bit less somewhere else which is always good.
Here is a run down on the parts for this VMware home lab build which should be capable of booting nested 64-bit VMs or as a stand alone ESXi host running other VMs since it is cheap (you can get almost 2 of these for the price of my 8-core build).
According to AMD, all Vishera series processors have the VT/RVI feature to allow you to boot 64-bit VMs in a nested hypervisor (http://goo.gl/jPkUMC) I’ll assume you will boot from USB, and that you have plenty of them from conferences past to keep my price under $800 :)
That is a grand total $687 US (as of 4/20/2016 pricing). Additionally there is currently $40 in mail in rebates ($20 each on the PSU and MB) so in the short term that is $647!