How long for cloning?

[dnanian]

Something really sounds wrong with the hardware, Boris. It's hard to say what, but this just isn't even remotely normal...

I'd stop it, then try booting in Safe Mode (hold down shift, and keep it down, during power on & boot up). Then, give it another shot.

If that doesn't help, I'd try erasing and zeroing the destination drive's data and free space. Maybe it's having a lot of retries?