All material on Sollecito's compter was recovered. There was no physical evidence of tampering, no evidence that the damage was deliberate.
Maybe I missed it, and I have tried to research this before, but did the police "computer experts" explain what exactly they were doing procedurally that shocked the circuit boards on each of the four hard drives? It seems they would have, given their general crystal clear transparency. All I found was Prof. Massimo Bernaschi's report on the initial data recovery effort (post shocking) in 2008 (available on http://www.injusticeinperugia.org/PDF-Files.html).
It was an either a silly little accident, that happened four times due to police incompetence (which should have lead to firings), or it was a deliberate act (likely leading to promotions). Hard drives don't shock themselves. And whatever shock-treatment-forensics-analysis they were attempting, it seemed to be more effective on Amanda's hard drive, for which the data could not be recovered. I guess that was an accident too.
-sd