Connecting IDE drives in G3 Macs: a potential problem

Recently, we covered an issue with connecting Zip drives that mentioned Master and Slave positions on an IDE/ATAPI bus. Essentially, if two devices are on the same bus; one must be designated the "master" while the other is the "slave." This master/slave issue has now come up again in a different context:

Ken Gruberman reports that when installing the 9.4 gig IBM UltraDMA ATA drives in the original G3 Macs, some worked while others did not. The problem seemed to be that the drive was placed in the slave position, but some G3s would not allow this. Ken was told by an Apple Tech Support person that "There is only one way to tell if a certain G3 will allow using an UltraDMA ATA drive as a slave device: look at the logic board, and find the video chip (ASIC) on the board. It should be about an inch from the built-in video port on the back. If the chip reads 'ATI 3D Rage II DVD' the computer will not support a 2nd ATA device. If the chip reads 'ATI 3D Rage Pro PCI' the Mac will support a 2nd device on the ATA ribbon." This problem does not occur with the new G3/BW Macs. [Overall, this appears related to differences in the G3 logic board revisions (as mentioned here previously). Also, MacInTouch posted a series of email messages on this topic awhile back.]

Update: A reader notes: "A far simpler way to check is to open up Apple System Profiler and check out what kind of graphics it claims you have. It should specify Rage II or Pro, without the complication of cracking open your computer and straining your eyes on the small type on the graphics chip."