Help identify unknown L2 cache card for Power Macintosh 6100.

[theirongiant]

Hello,

I bought a used PowerMac 6100/66 that was listed as "power on test only" and it made a chime. It had a working hard drive with System 7.6 installed. I've since connected a BlueSCSI and obtained an HDI-45 adapter to get a picture and run some tests.

There were two sticks of L2 cache inside the computer.

One was produced by LROG with manufacturer part number "LROG432-03," and also marked with Apple P/N 341-0741, indicating 256 KB L2 cache.

The other cache module has 160 pins and fits into the slot, but the PowerMac 6100/66 would not boot with this card installed by itself.

Photos below include macro shots of each chip on the cache module. For your convenience I have included a brief description of each sub-component or notable feature, and its accompanying text.

Printed on PCB edge:
APPLE COMPUTER, INC.
256K CACHE SIMM

Printed on PCB edge, reverse side:
MADE IN THAILAND

Sticker on a SIMM module:
For use on 6100 only

Sticker on another SIMM module:
CYM9233PM
9505703


Large square chips (U1-U2):
CY7B181-12NC
A15174 9450

Individual SIMM chips (U3-U10):
CY7C193-22VC
9502 200379

Small square chips (U11-U12):

U11:
(AMD logo) PALCE
16V8H-5JC/5
9434EBA A
M31-00014

U12:
(AMD logo) PALCE
16V8H-7JC/5
9446 BBM B
M31-00015

Small rectangular chip (U13):
CY74FCT244ATSOC
9420

These came from a donor/spare-parts 6100 where the ABS plastic was as broken as Mr. Glass from "Invincible." I managed to acquire a second PM6100/66 that was in much better shape for very little money, and will be combining parts from both systems to make the best possible low end Mac, and sending the worst one off to e-waste.

 

[phipli]

Hello,

I bought a used PowerMac 6100/66 that was listed as "power on test only" and it made a chime. It had a working hard drive with System 7.6 installed. I've since connected a BlueSCSI and obtained an HDI-45 adapter to get a picture and run some tests.

There were two sticks of L2 cache inside the computer.

One was produced by LROG with manufacturer part number "LROG432-03," and also marked with Apple P/N 341-0741, indicating 256 KB L2 cache.

The other cache module has 160 pins and fits into the slot, but the PowerMac 6100/66 would not boot with this card installed by itself.

Photos below include macro shots of each chip on the cache module. For your convenience I have included a brief description of each sub-component or notable feature, and its accompanying text.

Printed on PCB edge:
APPLE COMPUTER, INC.
256K CACHE SIMM

Printed on PCB edge, reverse side:
MADE IN THAILAND

Sticker on a SIMM module:
For use on 6100 only

Sticker on another SIMM module:
CYM9233PM
9505703


Large square chips (U1-U2):
CY7B181-12NC
A15174 9450

Individual SIMM chips (U3-U10):
CY7C193-22VC
9502 200379

Small square chips (U11-U12):

U11:
(AMD logo) PALCE
16V8H-5JC/5
9434EBA A
M31-00014

U12:
(AMD logo) PALCE
16V8H-7JC/5
9446 BBM B
M31-00015

Small rectangular chip (U13):
CY74FCT244ATSOC
9420

These came from a donor/spare-parts 6100 where the ABS plastic was as broken as Mr. Glass from "Invincible." I managed to acquire a second PM6100/66 that was in much better shape for very little money, and will be combining parts from both systems to make the best possible low end Mac, and sending the worst one off to e-waste.

341-0741 is a ROM not a Cache.

The machine will boot with just a ROM installed, but it wont boot with just an L2 Cache installed. They both have the same connector and you can actually swap their positions, although if you look at the silkscreen, one slot says Cache and the other says ROM.

 

[theirongiant]

Thanks. Another colleague saw my post and pinged me about the fact that the slot closest to the NuBus slot is actually ROM.

In the configuration shown below, I was able to get the Mac to boot and recognize 256 KB of L2 cache. Speedometer 4 benchmarks shows a ~30% increase in graphics performance with the cache installed. It's a noticeable difference.

 

[eric]

This might be of interest (if it's there, if it's not cc: @Fizzbinn )

https://tinkerdifferent.com/resources/ppc-macintosh-l2-cache-modules.19/