I am wanting to totally upgrade my B&W G3 Rev. A. So what I want to ask is will there be any noticable difference between a 1Ghz G3 and a 1Ghz G4? I currently am leaning toward the G3 because of the price. I will be maxing out the RAM. Also what is the best video card that these machines can use? I will also be buying a SATA Hard drive controler does anyone have any recomendations of a particular card? Is there any other useful upgrades that I haven't thought of. and if it matters for the CPU I will be dual booting 10.3.9 and OS 9.2.2.
I went down that road a few years ago with my G4. I find that the more residual value there is in the CPU you're upgrading, the more worthwhile the upgrade is. My G4 ad some value, so installing the 1.2Ghz G4 and the GeForce Titanium card and maxing the ram (1.5 GB) was worth my while. I can still use it todayy with 10.4.10, and with a 20" Apple Cinema display and a 15" Apple Studio display hooked up.
Sadly, B&W G3s don't have much residual value any more. They can be picked up for just a hundred bucks or so...
Why is that important? Well, why sink close to $1000 into a machine that simply isn't worth $100?
The other poster mentioned a Mini. That might be a good way to go, but if you have to boot 9.2, then you haved to be sure you get the PPC version.
But there are other options as well. Look for later G4s on eBay. You may find one that's already been upgraded, or came with a better CPU, Ram, etc. Stick with the "Quicksilver" or "Mirrored Drive Door" models, and you probably can't go wrong. There was a dial 1.25 Ghz MDD unit for an opening bid of $699. Unless you're getting your upgrade parts free or nearly so, that is a hard to beat price.
The big thing that'll be the bottleneck is how much RAM you cam put in. I wish I could put more into my G4, but 1.5 works fine most of the time, so long as I don't have too many things open at once. Any machine you can install 2 or more into is a better machine to start off with going down the upgrade path.
Good luck!