Date: Thu, 20 Nov 2003 07:42:54 -0600 Subject: Re: G3 Revision From: "R. A. Cantrell" <[EMAIL PROTECTED]> Message-ID: <[EMAIL PROTECTED]> In-Reply-To: <[EMAIL PROTECTED]>
Not surprisingly, I have some confusion among the terms ROM, MoBo, and machine in trying to determine which whatever I have. Is the ROM version as displayed in System Profiler and description of the small ROM card that lives on the board? or of the board? or both? If I understand correctly, the big problem in G3's is that the Rev. 1 (MoBo or ROM?) will not support Master/Slave IDE drives thereby limiting the machine to 2 IDE devices run off the native equipment. Some kind lister put up the designators for the rev a,b, &c Rom's recently, but I don't know yet if moving a rev 2 rom card to a (whatever you would designate it) board that originally had a rev 1 ROM would solve the master/slave dilemma. Is there a big bene for moving from rev 2 to rev 3? etc., etc., etc. More light?
When the machines shipped you could be fairly certain of the revision of your Beige G3 by the ROM revision. However, the ROM is on a DIMM and is easy to move, so in this day, the ROM version doesn't really tell you anything about the machine in which it is installed, because they are so easy to move from machine to machine.
There isn't a "problem" with the IDE busses in the sense of a defect. They work the way Apple intended. It's just that machines with a Rev. A ROM only support one device per IDE bus. Machines with later revision ROMs support two devices per IDE bus, which can be more convenient. However, the IDE in the Beige G3s top out at 16 MB/s, so if you have fast hard drives you may wish to install an ATA card in a PCI slot. The drives that shipped with the Beige G3s are old enough that they won't out-run the built-in IDE in performance, so there's no point in faster IDE interfaces if you're using a stock drive.
The deciding factor for two drives per IDE bus is the ROM. So, if you replace the Rev. A ROM in any machine with a Rev. B or Rev. C (or rare later revision) you will enjoy support for two devices per IDE bus. The motherboard revision has no impact on this quality. Later ROMs are available on Ebay and the price has dropped considerable this year. At the beginning of this year, I was able to sell several per week for $65 each. My last auction to close (about a week ago) closed under $20.
The only significant difference I've found between the Rev. B and Rev. C ROM is that the Rev. C does not work well (or at all) with some of the Skyline brand ethernet or wireless ethernet products. The other difference is that folks were paying about 30% more for the Rev. C for some reason.
Later revision motherboards for the Beige G3 had an updated faster video chip. I think the Rev. A had a Rage II, and the later versions had Rage Pro. The Rev. C may have had Rage Pro Turbo (may have the 'Pro' and the 'Turbo' backwards). However, there's no difference between having a Rage Pro and a Rage Pro Turbo as Apple didn't implement any of the improvements of the slightly later chip.
Some folks claim that the Grackle chip on the later revisions was better/stronger/faster, but I have yet to see convincing evidence of this claim. Grackle is simply a Motorola MPC106 chip. It comes in 66 MHz and 83 MHz flavors and a couple of versions which support or don't support more ratios of bus speed to PCI speed. There may also have been some later bug-fixed revisions I suppose, but I've never seen a clear, comprehensive claim of what quality a later revision Beige board has in Grackle that an earlier Beige lacks.
In fact, looking through the bin of motherboards at Goodwill, I find that the Rev. A Beige G3 boards with the Rage II video are more likely to have the 83 MHz Grackle than the Rev. B/C boards with the Rage Pro video. Specifically, I find that none of the later boards have the 83 MHz Grackle and many, but not all of the early boards have the 83 MHz Grackle. I wonder if there is a board out there with the 83 MHz Grackle and Rage Pro video.
Jeff Walther
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