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CountDown G5 Enables Mac OS 9 Booting for Power Mac G5s

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The French start-up software company Freedom Technologies today announced the immediate availability of CountDown G5, a controversial firmware update which enables users to start up Apple’s Power Mac G5 systems using either Mac OS 9 or Mac OS X.

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As shipped by Apple, Power Mac G5 systems can start up using only Mac OS X (although they can run older software in the Classic environment). But now, Mac OS 9 users can enjoy the performance and raw power of the Power Mac G5 system if they do not want to use Mac OS X, or are still among those users for whom Mac OS X versions of needed software are not yet available. CountDown G5’s methods are not subtle, and using CountDown G5 to create a Mac OS 9-bootable system could leave you with an unsupported hybrid machine, jeopardize your warranty, or create unexpected problems with future operating system updates. However, if you simply must have G5 power within Mac OS 9 – and if the Mac OS X Classic environment doesn’t cut the mustard – then CountDown G5 is your only option.

How CountDown G5 Works — CountDown G5 updates the Power Mac G5 firmware to allow the machine to start up using Mac OS 9 as well as Mac OS X – following the update, the Power Mac G5 will recognize bootable Mac OS 9.2.2 volumes as viable startup volumes, as well as volumes with Mac OS X 10.2.7 or newer installed. CountDown G5’s method of updating the Power Mac G5’s firmware is exactly the same as that which Apple would use if a flaw or incompatibility necessitated a change (such as the firmware updates issued for early iMacs, without which installing Mac OS X 10.2 or higher can render a machine inoperable).


Despite all the new subsystems and processor technologies in the Power Mac G5s, Freedom Technologies learned that the systems’ firmware packages aren’t terribly different from firmware shipped in Mac OS 9-compatible machines. Using careful black-box reverse engineering, they were able to determine which portions of the Power Mac G5 firmware needed to be changed to provide Mac OS 9 compatibility, and exactly what those changes should be. Although Apple did not perform extensive compatibility testing of the Power Mac G5 hardware from Mac OS 9 – since they anticipated all access would be moderated by Mac OS X – Freedom Technologies engineers reported discovering no significant problems accessing all the Power Mac’s features from Mac OS 9, in part because many of the new technologies (including FireWire 800 and USB 2.0) are based on open standards for which complete technical specifications are available. According to CountDown G5’s lead developer, in the handful of instances where incompatibilities were found, working around them was only a small portion of the engineering effort.

When started up from Mac OS 9, however, Power Mac G5 systems do not take advantage of the G5 processor’s native 64-bit mode: Apple would need to rewrite Mac OS 9 for 64-bit compatibility, and it goes without saying that Apple is expending virtually no development resources on Mac OS 9 these days. Similarly, Freedom Technologies cannot guarantee any particular driver or peripheral will work with G5 systems booting Mac OS 9, since they have no control over how third party vendors developed their software drivers. CountDown’s release notes cover cases of known incompatibilities (currently a handful of USB printers and digital cameras).

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T Minus 10 — CountDown G5 installs from its own CD-ROM: users insert the disk, restart while pressing C, and respond to the prompts once the system starts up. The installer is emphatic about confirming that the user understands the nature of the CountDown G5 product and is certain they wish to install it: you cannot mindlessly click through the CountDown G5 installer or walk through quickly by pressing Return. Default buttons and the nature of dialogs change, and users must successfully answer a quiz (as well as input a serial number) to install the product.

The reason for these extreme precautions is simple: once you install CountDown G5, there’s no going back. Freedom Technologies cannot legally provide Apple’s default firmware as an uninstall option, and Apple itself provides no way to re-install the firmware which ships on Power Mac G5 systems. Installing CountDown G5 is a one-way ticket, and users would be well-advised to do it only when plugged into a UPS: if the power were to fail during the two-minute installation process, there may be no way to recover the Power Mac G5 without replacing the motherboard.

Users should also note that installing CountDown G5 in all likelihood voids Apple’s warranty, although Apple has not yet made a formal statement on the subject. Similarly, warranties of third-party hardware products may not apply to CountDown G5-enabled systems. In particular, Macintosh peripherals developed with only Mac OS X in mind are extremely unlikely to work under Mac OS 9, even on G5 systems running CountDown G5, since no Mac OS 9 drivers will be available for those devices. Examples include third-party mice and input devices, scanners, and printers, although some devices (such as external hard drives) which are Mac OS 9-compatible should work without a hitch.

Lift Off! CountDown G5 1.0 is presently available only for Apple’s Power Mac G5 systems and will refuse to install on any other Apple hardware. Freedom Technologies says they’re looking into producing versions of CountDown for modern iMacs as well as Apple’s high-end laptops, but their focus is on Apple’s professional Power Mac G5 users. Freedom Technologies will have to update CountDown for any new Power Mac G5 systems Apple releases, as well as for any firmware revisions Apple slips into its production cycle. Freedom Technologies offers a tiny application (a 240K download) which reveals whether CountDown is compatible with the firmware in a particular Power Mac G5 system.

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CountDown G5 1.0 is available immediately to citizens of E.U. member states for 50 euros; U.S. citizens must pay an additional technology export duty which will bring the total cost to between $95 and $110, depending on currency values and the status of technology trade agreements. CountDown G5 is available only on serialized CD-ROM; there is no downloadable version.


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