Hard drive question...?

[Earth]

Hello All

For some reason my computer wont detect my hard drive. When I Try to boot it would even show up on bios..

I don't know if its dead or not. Is there any thing I can try to get my bios to detect it ? Or Is there any Free software that might be able to save it ?

I had three hard drives that all worked then all of a sudden none of them will get detected...

Thanks in advance,,,