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macrumors 65816
Original poster
Aug 10, 2012
Just picked up my 2nd Power Mac G3 B&W and with some research discovered it was a Rev A 400MHZ. My other one is a 400MHZ rev B. They both came with the same hardware installed. I am curious as to what other differences if any are there between them.


The rev A is on the left
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macrumors G3
May 3, 2014
The primary ATA controller in the Rev. A is "touchy" with two HDDs, while the Rev. B is fine with them. In reflection of this, most Rev. As shipped with a single hard drive bracket, while the Bs generally shipped with the dual-stack bracket seen on towers up through the Quicksilver.

The Bs have larger heatsinks-I've favored them for G4 upgrades for this reason.

Finally, anecdotally I've found that the Rage 128 in the Rev. B generally comes with the DVD decoder board, while the Rev. A lacks this, although I don't know if this is universally true.


macrumors 68020
Jul 25, 2008
Central US
Since 2003 I've had 4 B&W G3's in my possession. Somehow they have all managed to be Rev A systems. The only one with the DVD decoder board on the Rage 128 was the one that came with a DVD-ROM drive and the others lacked that add-on since they all came with CD-ROMs. Like Bunn said, the HDD bracket on the Rev B's is built to stack drives while the Rev A is a single level bracket that allows for 3 drives mounted along the bottom of the machine. That is probably the most easily identifiable difference between the models. I've never faced any data corruption running multiple drives in the one machine that I used nonstop from March 03-April 05. I still use it, but with one HDD in it now. More than likely I was just lucky.
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