Powerbook 1400 16mb ram module upgrade to 24mb

[EtherRad]

I have a 16mb ram module for the 1400c and I cannot find any 24mb ram modules. Would it be possible to add the 4 needed chips and some kind of connection at C3 to change 16mb to 24mb? It looks like there are some online warehouses that have KM48C2100BS-L6 chips.

 

[Trash80toHP_Mini]

AFAIK it should work one way or another. Which factory module do you have on board?

 

[EtherRad]

I have the 16mb original to the motherboard. I'm hoping to change this specific ram card to 24mb up from 16mb by soldering on extra chips.

 

[trag]

I would get a datasheet for those memory chips.  That will give you a pinout -- which pins have which functions.  Then get out the multimeter and trace out which pins those resistors connect to and what they connect them to.    Are they doing something simple like pulling up/down chip enable?   If so, you'll need to install the two unpopulated resistors probably.   Or are they doing something more or less complicated?

The unpopulated capacitors are almost certainly straightforward.  They're just there as voltage smoothing ("bypass") and when you install the next two chips, install the corresponding capacitors to smooth the voltage for those chips.

 

[Bunsen]

If you can find a good image of the 24MB module, that should answer a few questions for you.

 

[Trash80toHP_Mini]

Is that card OEM or third party? I need to root through the 1400 stack for a few parts again, so I'll try to find matching modules for a photo shoot.

 

[EtherRad]

third party I believe.

 

[Trash80toHP_Mini]

I guess that was a silly question on my part. IIRC Apple only supplied 12MB and 16MB factory slot cards. Yours must be for the user slot given its size. Did they offer memory upgrade cards as well?

 

[FacnyFreddy]

The other option would be to use a "donor" 16MB card and grab the chips and resistors/capacitors from it. I've heard of this being done with Toshiba notebook RAM modules in the late 90s.

 

[mtm84]

Got 80 bucks? http://www.memoryx.com/pb140024.html

Though I would call or email them first, they don't always actually have items in stock when they say they do.  That's the price you pay for making your own ram I guess.

 

[explit]

I have 1x 24MB Module for 1400c and 32MB + 16MB PiggyBack. If interesting - ping me. Will be much cheaper than 80 $

 

[gpbonneau]

If you can find a good image of the 24MB module, that should answer a few questions for you.

 

[ClassicMac]

I have some extra RAM modules that I dont need (they are two and add up to 52 megs of ram I believe). I dont need them since I have my 1400 maxed out on RAM on another stick and have a g3 upgrade. 

LMK dont need them

 

[august125]

I have some extra RAM modules that I dont need (they are two and add up to 52 megs of ram I believe). I dont need them since I have my 1400 maxed out on RAM on another stick and have a g3 upgrade. 

LMK dont need them

Did anyone take you up on this? I have a 1400c/166 with the minimum memory configuration of 16MB and can't find memory modules anywhere. I tried to message you directly but the site would not allow me to.

 

[EtherRad]

For some reason I never saw the last couple of replies to this thread as they stopped going to my email. I found some on buyee.jp and they work!