• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

unknown 'fat'-chipped module?

chelseayr

Well-known member
I realized it seem a bit odd for a ram (beside it doesn't match up with the one sdram dimm I still have on hand) and the notches doesn't match up to the L2 caches I still have to test someday either so...

it has eight of these fat chips (4 per side) in name of: motorola MCM62940BFN14 NQQY J9438
and there is a white label stuck to one of the chip and it says: SCM72MA32SG14 ATATJA9444

and in the middle equally on both sides is: cypress CY7B181-12NC A07299 9426

may be or not be much help but it has 160 pins total (60+50+50 fingered as I counted on one side and then doubled that)

thanks to whoever could happily tell me what this thing was suppose to be
 

chelseayr

Well-known member
mos8_030 mm..well..unless theres two different kind of L2 slots physically I'm not so certain about that suggestion you know? sorry, thanks still
 

chelseayr

Well-known member
above one is a L2 card I had handy and the below one is the unknown one in question. and as you can see whichever way you try flip it the unknown one clearly is not for L2 slot (I really doubt its any kind of rom card..or could I be wrong..hmm..)
DSC_9331.JPG
 

jessenator

Well-known member
unless theres two different kind of L2 slots
the PCI Power Mac series had one kind of connector which is the topmost specimen in your image, the x400/x500 (and the 6360) had a different pin arrangement in their connector:
1645978698006.png

And ISTR that the NuBus Power Macs also did, which might be the specimen at the bottom in your photo.

Unless it's not from a Mac at all...
 

Fizzbinn

Well-known member
I realized it seem a bit odd for a ram (beside it doesn't match up with the one sdram dimm I still have on hand) and the notches doesn't match up to the L2 caches I still have to test someday either so...

it has eight of these fat chips (4 per side) in name of: motorola MCM62940BFN14 NQQY J9438
and there is a white label stuck to one of the chip and it says: SCM72MA32SG14 ATATJA9444

and in the middle equally on both sides is: cypress CY7B181-12NC A07299 9426

may be or not be much help but it has 160 pins total (60+50+50 fingered as I counted on one side and then doubled that)

thanks to whoever could happily tell me what this thing was suppose to be

I’m aware of 4 different types of PPC Mac 160 pin Cache DIMMs you can identify via their pin groupings (counted on one side here):

6100/7100/8100
Pin groupings: 30 - 25 - 25

5200/5300/6200/6300
Pin groupings: 30 - 25 - 25
(Combo ROM/L2 Cache modules)

4400/6360/5400/5500/6400/6500/TAM
Pin groupings: 35 - 25 - 20

7200/7300/7500/7600/8500/8600
Pin groupings: 25 - 35 - 20


Looks like the one you have could be either the first or the second, are there ROM chips on the other side?
 

chelseayr

Well-known member
ah now I see. had not quite realized the physical slot changed a few times (compared to that ram is just either 72 or 168 in a manner speaking)

and as for the 'other side' its an exact mirror of what you see in photo except for the white label itself. so I'm going to assume that this means its a possible cache card for the x100 grouping since these had a separate adjacent rom slot yes?

(and mos8_030, consider me reeducated in a friendly way!)
 

Franklinstein

Well-known member
There is also a fifth type of module, for some of the later 100-120MHz 5xxx/6xxx series (non-PCI) that didn't have the ROM on the L2 cache module, so it was basically identical to a x100-series PM L2 cache. However it isn't electrically compatible with the x100 series; it works only in the late-model 5/6xxxx series.
I haven't looked too in-depth to determine what the differences between the x100 and these 5/6xxxx modules are but it would be nice if I could figure it out so I could modify an x100 L2 cache module to work in one of the 5/6xxx models (the combo ROM/L2 modules don't work in the late-model boards). I have like 3 of these late-model boards and none have the L2 cache so they're a little pokey.
 
Top