In the mix of licensing specifics around ESXi/vSphere 5 is the idea that for a paid license you have a soft limit – the vRAM entitelment is a high-water mark over a period of time that you can exceed briefly if you keep an eye on the average. However, I’ve been told that the Essentials/Essentials Plus licensing is a hard limit at 192GB (which I doubt since they increased the limit right before RTM) and that the ESXi free version has a hard limit at 32GB.
I don’t have sufficient hardware to test the Ess/Ess+ limit but it’s easy to test the ESXi limit:
Fire up Workstation 8 and install ESXi 5.
Register at VMware.com and get a license key for ESXi (otherwise you get the eval license which is the equivalent of Enterprise Plus)
Build 5 VMs giving each 8GB of RAM.
Yes Virginia there really is a hard 32GB limit for the free version of ESXi.
Nevermind! I ran the datastore (which was approx 32GB) out of space which is what stopped me. By setting memory limits on the VMs I was able to exceed 32GB vRAM powered on.