Just as MacMan writes. It's OS 8.1, so you have it made if you can install 8.1 on the 190cs. You should not even need a crossover ethernet cable, since the MacBook has auto-MDX. It's better to treat the MacBook as the server to save it from the embarrassment of not recognizing the 190cs. I have a Q605 (8.1) and CRT iMac (10.4.10) so connected at the moment (through a LAN).

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