Second hard drive missing! help!

So, today I was using my computer, and all was well. Later on in the day, I had gone off to my cousins house. Well upon arriving back, I noticed that my HDD's light was always on, well that aroused suspicion, so I thought maybe some process was constantly using my main HDD, but nope, that wasn't the case. So I looked in Computer, and noticed that my second drive, being G, was missing from it. This is very alarming because I JUST had my computer looked at, I received it back on Friday and everything appeared to be working alright. I'm afraid to reboot my system because I fear I might not be able to get back on. What should I do? I even looked in disk management, my only drive is C that shows up still.

I suppose I should also note that I just had my Windows 7 reset also. So I'm scratching my head here, also, I just checked the cables and they appear to be secure on the 2nd hard disk.

Yeah, that's what I just did, I'm fine now. Also, I was talking to someone in a chat room and they said that the setting the hard drive to never sleep option is unneeded since it'll use it when it needs to.. but, if I did this it would prevent it from being missing? When it came back after I rebooted everything was fine, and all my data was fine too.

Update: Set turn off hard disk after never setting now.

It appears to be that way, thanks!

Should I download some drive checker tool to like check my 2nd hard drive to see if there's anything going on? The guy who looked at it said my drives were fine, but I'd kinda like to see for myself.

Alrighty, sounds good, I'll give that software a look :)

Everything appears to be fine, right? Or should I be concerned?