I tihnk my segadrive 500gb died?

Ok hi guys. Short story how this happened. So I was using Windows7 RC and I downloaded FireFox 3.5 I was playing with it. I put my rig to sleep, next morning I turn it on and it wasn't responsive so then I restarted it and I got error that my bootmsconfig is corrupted. I'm thinking its probably the FF3.5 somehow so I will just reinstall my OS. I reinstalled to my legit winwos vista 64bit and to my suprise I only see one hard drive. I looked into the bios and the bios sees only single hard drive too. *sad face* I have two 500gb segadrive barracudas if you guys need that info. So I was like maybe its a bad cable...? I swapped the sata cables around and still only one (C drive) showing and no ( D drive) showing at all. Do you guys have any other ideas how to check if the hard drive is compleatly dead? I mean I touched both of them and they are both warm to the touch so I'm thinking they are both working....Please help I'm running out of ideas folks I went to Device Manager and it still only shows one of two hard drives. ://///

Here are my complete specs:


*G.Skill 4gb ddr2 800 @954mhz
*Vista 64bit
*Intel Core2Quad q6600 @ 3.4ghz
*Antec TwelveHundred full tower case
*Silverstone 700w modular striker series
*Coolermaster v8 heatsink
*Power Color Ati 4870 1gb ddr5 edition (800core/1090memory)
*ASUS 20X DVD±R DVD Burner
*Seagate Barracuda 500gb HD (2x)
*P45 ASUS P5Q SE (bios rev. 803)
*Acer 22"



/complain

I have no idea. Im scared my second exact one will go out and then I will not be able to use my rig at all.