I'm not sure why you might think that a G4 daughtercard will not work in conjunction with a Kansas MLB if it truly is a Kansas. I put a Kansas MLB from a 9600 into an 8600/300MHz case (with the black space-filling flapdoodle removed from the 8600), but with an XLR8 ZIF G4/400MHz daughter-card. I left the A/V holes open for quite a while before I found a coverplate. I have a Sonnet (fixed) G4/800MHz in a 9600 (formerly 604ev/350MHz). Goes like the clappers. Your G4 card is of the correct form factor for the slot? As long as you have the correct software support for the G4 in place before you swap the daughtercards, and remember to do your CUDA hocus-pocus, you should have little trouble. Then install OS 9.2.2, or even as far as OS X 10.5 (I hear tell), and live happily ever after.

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