Possible problem with motherboard

I didn't see a category for computer problems so I'll just post it here.

My home-built computer has worked without any problems for several months and then all of sudden it won't boot.

It powers on, runs a memory check, detects the CD-ROM drives, and then hangs when it tries to detect the hard drives. I can't even get into BIOs to configure...I pressed Delete repeatedly and it would say that it is going to the configuration menu but it just hangs there.

I'm betting that it is the cheap motherboard that is causing the problem (I hope it is not the hard drives!)

My system setup is (I don't have the model numbers with me now, if it's relevant I will find out):

AMD Phenom Quad-core
ECI motherboard
4 gig memory
2 hard drives
2 DVD-Roms
Windows Vista 64bit

I would appreciate hearing any educated guess on what the problem could be and how to pin it down before I spend money on a new motherboard. Thanks!

No SATA cables were loose. I checked by disconnecting the hard drives one by one and the problem seems to be one of the hard drives. When it is connected, the system fails to get past the POST screen. Strange...it is a new hard drive and to have it die like that without a warning....bleh.

Any chance of recovering the data or getting it working?