Hello Village_Guy, thanks for contacting us through the Intel Communities.
In reality we haven't received reports of people using spinning hard drives with our NUCs, especially because most of the models only offer mSATA connection for Solid State Drives.
Some newer models like yours offer an extra SATA port and use a 2.5 inch SSD, but a 2.5 inch mechanical drive may work as well, however I haven’t test it.
I’m going to check if this behavior is expected or not. I’ll keep you posted.
I just tested the following devices on my NUC and these are the results:
Crucial SSD 2.5 was recognized.
Fujitsu HD 2.5 was recognized.
These 2 products use 5v.
The only device that did not work was a regular mechanical 3.5 hard drive, but once I connected the HD to a power supply, it worked without problems. These HDs required 12v.
We have received some post from customer who are experiencing the same behavior, please check the following thread Intel NUC D54250WYKH not recognizing 2.5 SATA drive (Samsung M9T)
I am not sure that it's a NUC problem as opposed to a Windows problem. I remember my old reliable XP systems spinning down their drives like clockwork. But my Win 7 systems always go to sleep before their HDs spin down, even though the HDs are set to spin down well before they sleep.
Have you observed the correct behavior with your other newer Windows systems?