Hi checksergio, thanks for the quick reply.
I did see that post during my Google-fu before posting. I scanned through it, but ultimately decided to skip it as:
that post described SCCM 2007/WinXP and my issue is with SCCM2012R2/Win7
consistency with new installs (I've verified three more machines this morning since my initial post). I'm leaning towards something server-side because of this (please correct me if I'm off here)
these computers are currently in production so I won't have immediate access to them to check some GUI-related settings.
That said, if those items don't preclude me, I'll be happy to try them. Let me know what you think, and if I need to, I'll make arrangements to get access to one of the machines.