I usually run Speccy to see what taxes my graphics card the most; it helps me to decide what game I play next or to go for a coffee until it cools down.
I'd been playing the moderately cool Civilisation V and, upon starting Speccy, I received a message like "can't connect to SPC.dll". This meant that processor temperatures did not appear, i.e. CPU, RAM and graphics.
As an experienced Windows user, I logged off and on, which solved the problem. Just posting in case others have the same problem or if further issues develop.
Peace.