With a PowerPC- based Mac, your OS X upgrade capability is to Leopard OS X 10.5(.8)
via a retail install DVD; with updates to that available by download from Apple Support.
• *Requirements for Mac OS X v10.5:*
http://support.apple.com/kb/HT3759
• *Mac OS X 10.5 - Technical Specifications:*
http://support.apple.com/kb/SP517
•
MacTracker - download: +read and compare+ specifications
http://mactracker.ca (also see
http://everymac.com specs)
The computer has to be capable of running the OS X version, to include adequate RAM
installed (probably to the maximum supported by the build model of computer) and also
a larger capacity replacement hard disk drive, to be rid of the likelihood of the original
HDD being near failure due to several years of use.
Also, when upgrading from one OS to another, a complete archive of the computer's
OS X and applications can be made on an external FireWire self-powered enclosure,
a boot-capable drive for a Clone. This is a method, among several, to upgrade and
to also keep use of the current system; but not have the older OS X in the computer.
{A hard disk drive upgrade could include a SSD solid-state 'drive' such as the new
Legacy SSD from OWC for the PATA/ATA computers; those which can't use SATA.
The same reseller also has a top-flight external enclosure with HDD inside, one
with its own power supply and various port options; capable of booting Mac OS X.}
With a new drive in the computer, the current drive could reside awhile in a FW enclosure.
Ultimately, the original computer's HDD (if not replaced already) would be best upgraded.
If you seek an upgrade beyond Mac OS X 10.5(.8) Leopard, that requires an Intel-based
Mac computer; there may be some enticing ideas in Apple's online Store pages; to also
include the Special Deals - refurbished and clearance items, as available.
• Apple - Support - *Mac OS X 10.5 Leopard* (support links, answers)
http://www.apple.com/support/leopard/
Leopard 10.5 DVDs are considered in short supply, and various sellers have bid the price
to some higher than rational numbers. However, you may still be able to get a full official
copy from Apple; call their 1-800-MY-APPLE main number & ask to speak with a product
specialist. You'd need Leopard 10.5 DVD ($129) in order to use your PPC G4 with the new
products and software available; and if you have an iPhone or iPad that needs OS X 10.5
mention that, too. In order to support new products & a newer iTunes, you'd need Leopard.
Since development continues, and the latest software focuses on recent OS X, the 10.6
Snow Leopard and Intel-based Macs appear to be the upgrade path; ahead to 10.7...
You could get a newer model computer; even 'special deals' Macs include a recent OS X.
{Before the rush, I was able to get two Leopard DVD install sets; one, free and the other, $10.
The idea was to upgrade two - of my four - G4 PPC Macs to 10.5.8; the other two stay 10.4.11.}
Good luck & happy computing! 🙂
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