Hmm.. not particularly that I noticed that in my windows 7 VM in 5.1. However, I did upgrade my hardware version of my VM to 9 after migrating it from 5.0. I did check on the tools and display driver status. They seem to be in order. Can you do a quick check on the same.?
Also, while refreshing the VM console, have a check on the vmware.log in the vm directory to see any suspicious messages.