iPod neither turning on, nor being recognised by iTunes

Hi there, wondering whether anyone has any idea how to get my iPod Classic up and running.

I recently replaced the hard drive with a 128GB SDXC CF card with iFlash adaptor. I've done this before on another iPod and it worked great, but this time I've ran into problems.

When I plugged the iPod into the PC and opened iTunes it asked me to restore the iPod which I did, however all it did was go through the process without actually doing anything to the iPod.

What's more, the PC then stopped recognising the iPod and therefore I haven't been able to attempt it again via iTunes.

Now the iPod does very little apart from when you restart it, you can see a faint light, however nothing else comes on the display. I've tried it with the original hard drive and I get the same results. I've also tried charging it for several hours which didn't make any difference either.

Any help would be greatly appreciated.