My mbp is showing some sever signs of disctress, namely slow and some applications just crash. This has only really started since the 10.6.6 upgrade, so I do not know if the problem is software or hardware. I would like to eliminate hardware before I spent a very long time (remember the mbp is slow) trying to install 10.6.7 Disk utility verify and authorization fix reveal things are "ok". I run these using the mbp original install disk. I have connected the mbp in T-mode and connected it to another mac, but hen I transfer files there re many i/o errors. Is there any test, check, analysis I can do to determine if the hard disk is really dud?