How Powerful of a machine do I need?

Question

I am a beginner software developer. I am looking to buy a used powerMac off eBay. How powerful of a machine do I need to run Leopard and XCode Developer Tools? I also might run iWeb, and maybe iMovie and iDVD.
NOTE:
I said a powerMac, but I may also go with a used eMac, or if I can find one, a very inexpensive Mac Mini.
Also, once I buy the powerMac, will it be expensive (more than $75) to upgrade the processor? Can I use a G5 processor in a G4 mac? One last question, can I use any DDR Ram and any IDE HD in it?

Answer 1

Are these the right questions to be asking? Should one look farther ahead? My wife's G3 iBook ran 10.4.0 very rapidly. It's now crawling along on 10.4.11. You'll need to upgrade 10.5, or even boot from different releases on DVDs. What you really want is a machine with the minimal requirements for 10.6. Nevertheless:-
These computers Apple claims are minimally suitable are six or seven years old: the minimal specs for 10.5 specifies 867 MHz, and the default Nvidia GeForce MX video card (I'm told) will run Tiger more like a snail.
http://docs.info.apple.com/article.html?artnum=25232
which came from
http://support.apple.com/specs/powermac/
and MacTracker.
Though your resolution isn't quoted for it, your number of columns are divisible by 8. Consequently, SwitchResX may allow you to create a custom, workable resolution for at least the Nvidia GeForce 6200 AGP card, which I believe is optimized for Apple's 2D & 3D software.
http://www.switchres.info/html/SRX/FAQ.html
At one point, around 2001 or 2002, the Apple keyboard with a power switch on it was replaced by USB keyboard & mouse. USB & Firewire 400 Mbps became 800 Mbps. The old Apple video port was replaced by VGA and DMI. More importantly, memory modules could be of mixed size, hard disks could be of mixed speed, and hard disks could be doubled in speed with striped RAID.
Later, the unacceptable Airport card was replaced by acceptable Airport Extreme. Bluetooth was added. If you don't want to upgrade these latter items by PCI card, check the specs. (Some PCI WiFi cards with antennae come with Bluetooth.)
You can upgrade memory, hard disks, and optical drive cheaply; but the others could nickel-and-dime you to death, if you really need them immediately. In my case, they can wait. (Mine has four USB 2.0 sockets on a PCI card.)
Processors are expensive, so you may want a computer that will just work, won't burn up, and is flexible enough to be slowly upgraded. MacOSX can compile very slowly, I sure, for the kernel uses messages rather than semaphores, so race conditions (crashes from being weighted down) don't occur. You may want a Power Mac with the above features. Here's a minimal machine on eBay (which has an L3 cache, I think), being sold very cheaply by a very reliable dealer:
http://cgi.ebay.com/Apple-PowerMac-Quicksilver-G4-867mhz-60-512-CDRW-Zip_W0QQite mZ300218642150QQihZ020QQcategoryZ111418QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
It's faster than my 800MHz. Mine had the video card replaced by the popular Nvidia GeForce 6200 (for the 5200 seemed buggy, I believe) for $50, less on eBay.
http://www.amazon.com/Nvidia-Geforce-Profile-Support-support/dp/tech-data/B000H0 0JO0/ref=deasmtd/105-0812408-5623635
Mine came with 256 MB video memory which it shares with the CPU's real memory, I believe. This, on my machine, has 2 of the 3 slots filled with 256 Mb modules; and a $20 eBay 512 module would bring it to at least 1 Gb. Mac OSX 1.5 relies heavily on virtual memory; if RAID will support virtual memory, I can buy a duplicate of my 60 GB disk for $20 and create an array that appears to rotate at 14 400 rpm. Disk space isn't a great problem, for mine came with a new, $40 Pioneer DL super- multi- optical disc writer.
Optical discs are where my data, such as iMovies & iPhotos, lie. (Ah, little pun there.) Also large applications, such as large or related applications are principally stored on LightScribe optical discs:
Free optical disc of Unix security applications
http://s-t-d.org/index.html
Free MacOSX applications run from optical media
http://www.freesmug.org/portableapps/
CinePaint for MacOSX
http://www.cinepaint.org/
If you're not writing a new operating system or office suite, and can afford the time for your frequent compiles, and need dual monitors (for testing your application on one, programming it and compiling it on another), an initially inexpensive Quicksilver has at least two fans and may have the features that will allow you to improve it with time.
My only suggestion is to research everything carefully. I hope some who have tried 10.5 on a minimal machine will respond.
Best of luck.
Bruce