Computer won't boot..can't find Drives

Hello,
Got a new computer at work so I brought the old computer home. All I did was unplug at one location and plug in at new location. The computer had been running onsite w/out monitors, keyboard, mouse for a week or more as I could just remote into it for the files. When I plug it in at home it stops at a black and white screen and says Drive 0 not found: Serial ATA, SATA-p
Drive 1 not found: Serial ATA, SATA-2
Drive 2 samsung dvd drive
Drive 3 philips dvd rw

When I hit F2 and go into the BIOS it shows: 1 usb floppy drive
2 sata hard drive not present
3 onboard ide harddrive not present
4 onboard usb cd rom drive
5 usb device not present

Why can't it find the hard drives to boot up my machine?