just recently introduced vsphere 4.1u1 hosts to a cluster and noticed an odd behavior. windows 7 vms were complaining about insufficient video ram. which doesn’t necessarily seem like a big deal, but in this case the vms would power off by themselves shortly after reporting the error. i tried setting the video ram to “auto”, but that didn’t resolve the issue. i finally just bumped up their video ram to 32MB and the problem has gone away. the resolution settings seemed normal on the vms…however i am unsure if aero was enabled (and thus causing the problem).