Thanks for help u0d102y. I will look into it. "Why should Apple replace the part only if some people has nearly sounded issue with the unit?" Apple should replace or repair the unit because according to the internet the issue is as common as the nVidia 8600gt issue in mcabook pro's. Do a search on "Unable to list FireWire devises" and/or "mbp nvidia 8600gt" and you will see what i mean. Apple has known about the problem for a long time. http://support.apple.com/kb/HT1317?viewl... Not an easy to find unless you you know what you are looking for and not indicating how serious the problem can be or that the logic board might have to be replaced. Think about it: On many Mac's the firewire is not working any more, just after the warranty is over. It sounds to me like cutting corners more than anything else.

I have the same problem on MBP Santa Rosa 4.1 15" After an attempt to start in target disk mode i found that the firewire is not working. Going to the System profiler->FireWire I get only "Unable to list FireWire devises" WITHOUT HAVING ANYTHING CONNECTED TO THE FIREWIRE PORT! 1.Clearing the pram does not clear the pram!! The clock values still keeps the time (made in swiss:)?? The track pad double click speed is the way it was...no indication of reseting at all. Yes yes I press CMD, ALT, P and R (Have had Mac's since Mac Performa) and the chimes are repeating just the way they should but no actual reset is done. 2. Zooming with the track pad did not work, but started working again after clean system install. 3. Powering off, removing the battery and pressing and holding the power button does not have any effect. 4. In the Console I saw a message "the firewire bus may be unstable" 5. In single user mode i can see that firewire gets registered with speed s100 instead of s 800 6. Run the apple hardware test....