Mac OS 9.1 and CD-RW on PB1400

... but I wouldn't call it "effectively." I had it running on mine (with 64MB RAM) years ago. Trouble was that 9.1 used about twice the RAM that 8.6 did. So I didn't keep it there for long.

As for the CD-RW question, I saw one at DV Warehouse (link) but it's a little spendy at $99. But most any small-format tray-load mechanism from a portable should work, with a little creative modding. If you pull the 1400's CD module apart, it contains a mechanism like what's used in other portables (Mac & PC), and have been used as aftermarket upgrades for the tray-load G3 iMacs. There might be a little more to swapping one out, and the outside plastic plate may or may fit, but the system should recognize it just fine.

Yes on MOS 9.1 - it's my choice for any PPC Macintosh with more than 32MB RAM and a modernish harddrive (say 4GB or better, for effective and useful virtual memory.) Others may (meh, will!!) disagree, but there's so much more PPC-native code in OS9 vs. 8.x and earlier ain't even funny.

As for the writable optical drive - You can add a standard formfactor optical to the 12x expansion bay module, but not to the 6x or 8x modules. See my relevant page for more details.

So that's not the problem - the real issue is finding a SW which will actually let you burn CDs. The only package of which I'm aware that allegedly works on the 1400's expansion bay atapi bus is "B's Recorder Gold" for which I've yet to find a source for a classic Mac version. Please let us know if you locate it, or any other SW package that can do the job with an internal CD/RW on a 1400.

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On actually going to the link I provided above, I find that you can in fact buy B's directly from the publisher. Costs US$50 and says it requires 9.2 or better. I'd buy and try, but I've long since stopped using my trusty 1400s . . .
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dan k