i'm no expert at all, just messed around a bit at home, but this is what i'd do:

if it's not in device manager then it needs to be. as said, try reconnecting it, although it sounds as if it is connected otherwise it wouldn't spin up etc.

if that doesn't find it, right click in device manager and scan for hardware changes to see if it picks it up. if it finds it, it will either automatically install the driver if present (unlikely, or it probably would have done it by now) or you will have to install it.

if it doesn't find it, you may be add it manually by going to 'add hardware' in the control panel.

also, on boot up it should be found in the BIOS before windows loads. you should get a prompt like 'F11' or something when you first fire it up that takes you into the BIOS. go in there and see if it can be found

EDIT - the yellow exclamation marks are because those bits of hardware are not working properly. maybe just need drivers re-installing or maybe a hardware fault