The same thing happened with my iMac G3, after spending hours of work on it I found the problem was the RAM (strange, isn't it?), also I had to reset the PMU.
look here http://support.apple.com/kb/HT1431
I think it's a coreaudio bug, the APIs are not responding.
Try with (as said before) the software restore, http://www.apple.com/iPhone/how-to/index.html#help.updating-and-restoring-iPhone-software
Are you sure it's a chip problem?
It could be the firmware, try restoring it and upgrading to the last version.
The problem started when you bought it?
This happens with some computers, I have the same problem. I'm not sure, but I think iPhones MUST be attached to USB2.0 ports, with a direct wire. Try with a hub too.
Well, the battery may be not connected (it can't charga/it can't gove energy/it isn't recognised), my sister's iPod showed the same problem, the one thing you have to do is to give it back, it's most probably a logic board problem, impossible to fix.
Does the iPhone work well? Have you tried with more cables? with any other computer? Maybe it can't give 2A of power to the USB port, try disconnecting all and connecting only the iPhone. Let me know...
You should reinstall Mac OSX by using the restore disks found in the box when you bought the mac, then restoring all your data from the old HD (using a sata adapter)
Wow, no chime, that's veeery bad! THat means the motherboard hadn't passed the self-check.
Have you done anything particular before the "death"? That's a problem that can't come out from nothing. If you want you can try an EPROM reset, by doing what is written here --> http://support.apple.com/kb/HT1379 Try even disconnecting the mac from power supply and keeping the power button held for some seconds (10-15)
Yes, that's PER disk, thank you.
Now I discovered that it's not enough illuminated... I have to buy a good lamp.
Thank you, corrections have been added to the guide!
Thank you so much! It's only my first guide, but I'm going to post fun stuff lately!
Please always watch for grammar mistakes!
WOW! Great work, Nintendo stuff is hard to open!