I have noticed that the hardware clock on my DC3217BY (the red NUC) always gets set to some random value in the future. Of course the OS after bootup takes care of things. I manually set the clock to the correct value in the BIOS (F2), but on the next restart, its back to its old tricks. Anyone else noticed this? I have not examined if i have a good button cell (where is it located) or not.
The CMOS backup battery is on the underside of the board, next to the CPU cooler shroud. Just take out the two screws holding the board in place, then lift it out.
Note where the two screws were when you take them out. You don't want to mistakenly put them back in the corner holes in the board as that's where the cover screws on.