PowerBook 500 Connector 'Destroyed Mold' - Just a Myth?

[croissantking]

It's common folklore that the connector for the CPU/Memory daughtercard of the PowerBook 500 Series was mysteriously discontinued back in the late 90's, preventing new upgrade cards from being manufactured.



I've always just assumed it was true, given the many sources that cite this. Here are some that I could find.

From a previous thread here:

From what I've read Newer Technologies was able to essentially drop in a 740 G3 in place of a 603e processor on one of their blackbird CPU daughterboards because they are apparently fully pin-compatible, However, by the time their 740 G3 prototypes were completed, the interfaces for the CPU daughterboards were no longer being produced, so the project was dead in the water.

Anyway supposedly the reason Newer didn't bring a 5x0 G3 upgrade to market is that the processor card connectors were discontinued and the molds were destroyed, either because AMP didn't want to keep them around or Apple requested their destruction

From 65scribe's video about the PowerBook 520 on Youtube, at about 7:20:

...the supplier of the daughtercard connector inexplicably destroyed the mould for it, meaning no more upgrade cards and no G3 upgrade card.

From a very old but highly informative archived Japanese website (I used Google to translate it):

The connector that connects the daughter card to the logic board...had been discontinued, and Newer was unable to secure enough of them...As a result, Newer realized that they would not be able to produce even the backordered items, so they removed this card from their list. This was in January 1998.

Now, I've been looking into this as I ponder a design for a Reloaded CPU card. The connector just seems to be a very standard 1.27mm pitch part, available from a multitude of different vendors. Here's one, here's another. I'll place an order soon to verify this, but from the measurements in the datasheet for the 87024-620LF connector it seems to match exactly.

I have a hypothesis that there has been a bit of confusion at some point, and what actually happened was that the RAM card interface (the 70-pin Metristack connector) was the part that was discontinued. It is a far more obscure design, doesn't seem to be available anywhere, and its unavailability would have similarly halted viable upgrades for the platform.

I'm curious to know as well where this claim about the destroyed mold originated.

 

[luRaichu]

I'm curious to know as well where this claim about the destroyed mold originated.

Low End Mac

 

[croissantking]

Low End Mac

Do you have a link or citation? Despite LEM's reputation for spreading misinformation, I searched the site and couldn't find anything.

 

[luRaichu]

I was shitting you

 

[herd]

...as I ponder a design for a Reloaded CPU card.

Are existing cards being killed off by something? Do they suffer from battery or capacitor corrosion?

 

[Phipli]

Are existing cards being killed off by something? Do they suffer from battery or capacitor corrosion?

I'd guess he is considering a PPC upgrade. But I'm curious to see

 

[croissantking]

Are existing cards being killed off by something? Do they suffer from battery or capacitor corrosion?

I'd guess he is considering a PPC upgrade. But I'm curious to see

I want to bake in some improvements, like having 16MB (or even the full 48MB addressable) onboard, 550c ROMs in a smaller TSOP48 package, and possibly a programmable clock generator set with DIP switches (if there’s space left over). I'd make a few of these available with full 040 CPUs for sale, a special run.

 

[herd]

Ahh, I see. Is there a source for those custom apple chips? The china warehouses sometimes have random stuff like that left over from production.

I would suggest calling it something besides "reloaded," because those projects have no interest in improving the design. If you don't want to simply call it an upgrade it would be fun to come up with a snazzy name.

Good luck with the project!

 

[frontein1]

I want to bake in some improvements, like having 16MB (or even the full 48MB addressable) onboard, 550c ROMs in a smaller TSOP48 package, and possibly a programmable clock generator set with DIP switches (if there’s space left over). I'd make a few of these available with full 040 CPUs for sale, a special run.

Cannot wait for this! Consider me already queued up

It might be really fun making the ROMs programmable, and building in a ROM disk and driver. I'd be happy to collab on this.

 

[aladds]

Could the unavailable part be the RAM connector, rather than the CPU connector? presumably that could be solved in a reloaded card by integrating as much RAM as will physically fit.

Edit: You mention this in your original post, I clearly cannot read

 

[croissantking]

Could the unavailable part be the RAM connector, rather than the CPU connector? presumably that could be solved in a reloaded card by integrating as much RAM as will physically fit.

Edit: You mention this in your original post, I clearly cannot read

There are three options that I see -

1/ Extend the footprint of the CPU card across the area usually reserved for the modem, and populate it with max RAM.

2/ Create a modern replacement RAM card that uses the standard footprint but with a readily available interconnect

3/ Harvest the original RAM connector from donor CPU cards

I would only do 3/ if no other source for the Pratt MemIC can be found, otherwise I'd probably go with 1/ - but anyone (*cough*@finkmac*cough*) who wants to send faxes to their PDA will be unhappy with that.

 

[croissantking]

I would suggest calling it something besides "reloaded," because those projects have no interest in improving the design. If you don't want to simply call it an upgrade it would be fun to come up with a snazzy name.

Good luck with the project!

Noted, and thanks You're right, the Reloaded name isn't quite correct for this project – don't want to be misleading, of course.

Cannot wait for this! Consider me already queued up

It might be really fun making the ROMs programmable, and building in a ROM disk and driver. I'd be happy to collab on this.

OK! We should talk about the ROM side of things, curious to know what you have in mind.