It's the same regardless of the method, disk to disk, partition to partition, disk to partition, etc.

You may have already covered these, but I'd also consider swapping IDE cable, checking PIO/DMA in BIOS, etc.

I see that dd is getting some attention from the feds for forensics-grade copying, FWIW.
_________________________
Jim


'Tis the exceptional fellow who lies awake at night thinking of his successes.