Well, I ran the system and memory diagnostics on my Mini 9 as Dell Tech support wanted me to do. Everything passed.
I happened upon a Windows 7 forum where someone mentioned the HD Audio Controller as a problem with overheating . I disabled it in Device Manager and found the Mini ran better and somewhat cooler. I found a newly released Vista 32bit drive for Realtek audio on Realtek website. It installed easily and I re-enabled the HD Audio in Device Manager ; now mini is running well, core temp reports 64C, Realtemp reports 30C. More importantly, the pc feels cool to the touch.
So I watch and wait. Maybe this is a solution for others running hot.
Can anyone tell me why RealTemp and CoreTemp are so far apart? Do they measure different parts? They both move in the same direction (when pc is hot to touch, they both rise, quickly).