MacBook Pro 2008 motherboard failed. Upon sending it to an Apple authorized repair center, they confirmed this. They gave me the laptop back so I could open 'er up and get the hard disk out, which I did. The hard disk should be undamaged.
However, upon plugging it into an external enclosure – and connecting the enclosure to a computer running Windows – there's power, but nothing seems to happen. I'm just powering over USB. I wouldn't expect the HDD to be dead as well as the motherboard.
Does the 2.5" SATA HDD from a 2008 MacBook Pro need extra power when connected in that way?