The vRAM entitlement was introduced with vSphere 5.0, but eliminated some time later. If you are still running an early version of vCenter Server 5.0 you may still be affected. To resolve this you'll need to update vCenter Server to at least Update 2 (see VMware vCenter Server 5.0 Update 2 Release Notes - "vCenter Essentials no longer enforces vRAM usage limit of 192 GB ")
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