PlainTalk is not supported on machines with the Power Macintosh Upgrade Card installed. This is because these machines do not support the new Sound Control Panel that is required for Speech Recognition. The PlainTalk Microphone is not compatible with these machines, and the original round Apple microphone does not work with PlainTalk. Because it is not possible to select the "Options" feature of "Sound In" in the Sound Control Panel, it is not possible to select the microphone.
The Power Macintosh Upgrade Card data sheets are not very clear about this. It does, however, tell you what you get with the Power Macintosh Upgrade Card. It then continues and states: "In addition, even greater performance, as well as speech and telephony capabilities, can be yours if you choose the appropriate Power Macintosh Logic Board Upgrade for your Macintosh." Thus, PlainTalk is supported with the Power Macintosh Logic Board Upgrade, and not with the Power Macintosh Upgrade Card.
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