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IDE in beige g3 question
Posted by: Green78II on 2010-01-09 20:14:47
I pulled out my power supply to clean it up a bit underneath, and I decided I would try to add an 80 conductor cable to my G3. However, I found that the connector is slightly different from the IDE found in a standard PC. Pin 20 appears to be used in the G3, but isn't on the drive itself. However, on the 80 conductor PC cable, there is nowhere for that pin to go. could I modify the pc cable so it will plug into the board, or could that damage my G3?

Edit: Clarified what I was talking about.

Posted by: Anonymous Freak on 2010-01-09 23:56:47
I pulled out my power supply to clean it up a bit underneath, and I decided I would try to add an 80 conductor cable to my G3. However, I found that the connector is slightly different from the IDE found in a standard PC. Pin 20 appears to be used in the G3, but isn't on the drive itself. However, on the 80 conductor PC cable, there is nowhere for that pin to go. could I modify the pc cable so it will plug into the board, or could that damage my G3?
Edit: Clarified what I was talking about.
The pin is disconnected by ATA standard. Most 80 conductor cables have it filled. See Wikipedia for info on the cables.

That said, unless you were having data corruption issues where you think it may have been the cable, an 80 conductor cable is unecessary on a G3, which only has ATA-3 DMA mode 2 - 16.7 MB/s. 80 conductor cables didn't even enter the standard until the next revision ATA-4 UDMA mode 2 - 33.3 MB/s, and didn't become at all 'required' until the one after that, ATA-5, UDMA mode 4 - 66.6 MB/s.

It is also 100% safe to modify either end. Apple didn't use the pin for anything custom, they just used a header with all the pins. If you want to ensure that you never plug the cable in backwards, you can snip the pin off the motherboard. Removing the filler from the cable is more difficult.

Posted by: Green78II on 2010-01-10 08:33:04
Thanks, I did a lot of looking, but I couldn't find anything that told what the standard was for IDE on the G3. I personally think the key pin is redundant as there is a key molded into the plug and the socket itself above pins 19 and 21.

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