PowerBook 2400c Cardbus mod

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Oct 19, 2021
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Has anyone ever done the Cardbus mod to a 2400c? I've read that removing the resistors at c375 and c377 will enable Cardbus (https://www.mail-archive.com/[email protected]/msg07636.html), but I've also read that these resistors should instead be replaced with different value resistors.

I love my new 2400c and I'm very afraid of attacking it with my soldering iron :) I'd really appreciate any insight or anecdotes!
 

Drake

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Sep 23, 2021
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Has anyone ever done the Cardbus mod to a 2400c? I've read that removing the resistors at c375 and c377 will enable Cardbus (https://www.mail-archive.com/[email protected]/msg07636.html), but I've also read that these resistors should instead be replaced with different value resistors.

I love my new 2400c and I'm very afraid of attacking it with my soldering iron :) I'd really appreciate any insight or anecdotes!

I did quite a bit of digging even using wayback to load up some dead links and the closest I got was a "upgrade" service for $99 haha. There are multiple references about the resistor removal or bypass but even so these old blog and forum posts lack any pictures. Hopefully someone can chime in, surely there are some 2400c owners brave enough to Guinea pig? Paging @Mac84
 

Mac84

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I did quite a bit of digging even using wayback to load up some dead links and the closest I got was a "upgrade" service for $99 haha. There are multiple references about the resistor removal or bypass but even so these old blog and forum posts lack any pictures. Hopefully someone can chime in, surely there are some 2400c owners brave enough to Guinea pig? Paging @Mac84
If either of my 2400 machines worked I'd gladly be the guinea pig... :(
 

This Does Not Compute

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From what I recall, the 2400/240 model officially supported CardBus, and considering that the machine has its CPU on a daughtercard, I'd be *really* surprised if Apple bothered to redesign the motherboard just for that feature.

Architecturally, the 2400 and 3400 are similar, and the 3400 also could do CardBus unofficially. Here's a page I found about it. I haven't tried on either of my own 2400s, but I suspect following those instructions would work as it sounds like, outside of the controller chip, what makes a machine CardBus-compliant largely comes down to the actual card cage.
 

KnobsNSwitches

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Nov 2, 2021
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I know I had also read in the past that snipping one of the yellow bodge wires (if present) on the motherboard is another way, but I can't find the link on that at the moment.
Seems there's no shortage of theories, but I'm with @This Does Not Compute, I would guess software + cage is really the only differences
 

This Does Not Compute

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So I had both of my 2400s out this weekend and remembered to test them for CardBus compatibility. In short: On the 180MHz model, nope. I tried hot-plugging a card in, and as soon as I did, the Finder crashed and reloaded. The machine kept running, but when I went to shut it down, it froze. I pulled power, plugged it back in, and when I hit the power button the hard disk spun up but the display never lit. I did the same thing on the second machine just to be sure, and it behaved the exact same way. I'm pretty sure there is indeed a hardware requirement, specifically a CardBus-compatible cage.

My best guess is that Apple was switching parts mid-run of the 3400's production, explaining why some machines work out of the box and others need to be upgraded. The 2400c/240 probably got listed as CardBus-compliant because by the time it went into production, Apple would have exhausted its supply of non-CardBus cages. At least, that's the most logical reason I can think of.