Any recommendation for new RAM chip for Mac 128k?

[AlpineRaven]

Good morning all, 

I need to get a new set of RAM for Macintosh 128k, I've came across to TMS4256-10NL which is 100ns RAM - would it work in 128k? Or it has to be 150ns?
Any other recommendation for it?
Cheers

AP

 

[techknight]

uniserver from maccaps sells a RAM kit for these, last I checked. 

Trag may have something as well. 

 

[Gorgonops]

Are you looking to upgrade to 512k or keep it at 128k? If it's the latter you'll want 4164s, not x256s. Just about any 150ns or faster chip should work, generally speaking faster rated memory is fine to sub for slower rated.

The 256kbit chips will technically work as subs for the 64k ones but obviously they won't be 'correct'.

 

[AlpineRaven]

Yep all good I am keeping it all original 128k. Currently it has been upgraded to 512k via slots (its not soldered - it has slots and the chips are pushed in)

So I've found 4164s and ordered.

Cheers

AP

 

[Gorgonops]

Remember, if you're reversing a 512k upgrade you'll also have to revert the changes to the addressing circuitry, and the exact details for that depend on the board revision and whos plan the original upgrader followed. It won't automagically detect that you've plugged in smaller chips.

 

[Trash80toHP_Mini]

I hope you've got an external FDD or the big tomatos's replacement for it. Otherwise,you're rendering that poor machine all but unusable by backtracking on that road.

edit: should'a put the 128K on the list of OCD inducing Macs. You guys are even nuttier than SE/30 upgrade fanatics.

 

[Gorgonops]

So far as I'm concerned the 512k Mac is actually the "Original". The machine Steve Jobs trotted out during the January 1984 dog-and-pony show was a prototype Fat Mac because they couldn't fit the demo into 128k.

 

[Trash80toHP_Mini]

Nope, the Plus has to be the first actual shipping unit. Floppy swapping on my 512K Beta release was almost intolerable.

 

[Gorgonops]

They should have filled the gigantic cavernous hole that was left over when they canned the Twiggy with two floppy drives instead of one. Problem solved.

 

[Boctor]

They should have filled the gigantic cavernous hole that was left over when they canned the Twiggy with two floppy drives instead of one. Problem solved.

Yeah, it's a sad story, the engineers wanted Macintosh to be cheap, so they could use one themselves. But no matter how much they saved on parts and manufacturing, the 1984 ad campaign raised the machine's prices like crazy. Or at least that's what the developers' short stories on Folklore.org say.