First of all you would need a PCI slot to run ProTools so it ain't gonna happen.
The drive is 4200RPM and there are other Audio programs like Logic Audio, Cubase
VST 5, etc. etc. etc. so if they run on a Powerbook with a 4200RPM drive then, it
should run fine. The amount of digital audio tracks that are availiable for recording
depends on the speed of the processor, and the hard drive. Faster drive and processor
mean more audio tracks for recording but midi should not matter too much. There are
a lot of new audio interfaces out now like the MOTU 828 Firewire or, Tascam 428 USB,
the Event EZ-Bus USB so, some of these new interfaces have both digital/analog and
midi ins and outs either Firewire or USB connections. Also there are software based
synthesizers and samplers loop editors and so on. This area is what the Mac platform
excels at audio and video recording and editing and the Mac has been the platform of
choice for professionals ever since the Atari ST. All the professional audio programs
are made for the Mac and then ported to the PC so the PC has always been a lower
priority for the makers of these programs. Sonic Solutions is only on the Mac, ProTools
plugins and third party software are mostly for the Mac But, there are some good
software programs for the PC like Gigasampler. I've always been on the Mac because
of the software that I need to use and its the best platform for audio and video and it does
other things quite well too.
Markus