The time to buy a used PCI Power
Mac might be now. With Mac OS X requiring a G3 or faster,
people are starting to dispose of their pre-G3 PCI Power Macs.
While these are aging, they still can be great backup machines.
I use a 9600/233 in my room for basic
Internet, email, and word processing, which is completely within
the capabilities of the machine. In fact, it even does a decent job
with graphics applications and playing back QuickTime movies.
That was at the top of the line of the pre-G3 PCI Macs, but what
about the other end? I am leaving out the 7200, since this machine did not use daughter cards and had a different logic
board than the rest of the PCI models.
At the lower end of the spectrum were the 7500 and 7600.
The 7500 offered AV ports, and a 100 MHz PowerPC 601 processor -
the only daughter card upgradeable Power Mac to use a 601. The 7600
used a 604 processor running at 120, 132, or 200 MHz, which is
actually quite a bit more powerful than the 7500's 100 MHz 601.
Other than the processor, AV jacks, and label on the front, the
7600 logic board is the same as the one in the 7500.
These older Power Macs can really be great machines if upgraded
correctly. Does this mean sticking in a G4 and adding a 80 GB hard
drive? Not necessarily. In fact, you may be able to make do with
the stock processor or another 604e at a higher MHz rating.
I have a 7500 set up downstairs, which my sister uses for
Internet access and homework assignments. It was upgraded was a 200
MHz 604e processor, 112 MB of RAM, and 1 GB and 2 GB hard
drives. It runs well, and its performance surprises me. I am
constantly amazed when my sister downloads the latest movie
trailer, and I see it playing smoothly on a six-year-old computer.
It also amazes me to see her running the visualizations in iTunes -
full screen - with very little slowdown.
I use my 9600 for much simpler tasks. The majority of the time I
am typing up research papers or other homework, and I am often
running AOL Instant Messenger, Netscape, or Internet Explorer in
the background. I see zero slowdown, except for the fact that the
Internet connection that this machine uses is not optimal (a 33.6
modem).
Out of curiosity, I decided to try the game "The Sims" on my
9600. The requirements state that the game 
requires a G3 at 233 MHz or faster, 64 MB RAM
with virtual memory (128 recommended), and a 2 MB accelerated
video card ( 4 MB recommended). I installed the program and
soon found that it ran better on my 9600 than it had on my old
beige G3! Not only was the video faster, but the game loaded faster
in general, and things felt much more responsive.
That sold me on the power of the 604e processor. While it's not
for power users who need G3 or G4 power, it's an excellent choice
if you just need a backup machine for the Internet.
My recommendation for a decent pre-G3 Power Mac would be a used
7500, upgraded with a 200 or 233 MHz 604e processor (Apple's 300
and 350 MHz versions only work in the 9600/300 and 9600/350)
and at least 96 MB of RAM. Load OS 9.1, and you've got a great
machine for Web browsing, which will be able to access any site
that your newer G3 or G4 can.
If you don't mind spending more, the 8600 or 9600 series are excellent. The case
is simply amazing in terms of ease of upgrading, and there is room
on the front for three drives - and more room inside for hard
drives. The 9600 comes with 6 PCI slots, so you have very few
limits to expandability. This unfortunately keeps 9600 prices high,
as Apple has yet to produce another Mac with 6 PCI slots, which
some people actually need.
Don't pay over $300 for a used 9600/233, and don't pay over $100
for a 7500. Often you can get 7500's for as little as $50 with no
RAM or hard drive. The 8500 and 8600 fall in the middle, selling at
about $150 and $250, respectively.
There is a pre-G3 PCI Power Mac for almost every budget. If you
need a second computer, one of these machines might be perfect.
