The goal for this resource article is to document identification and reference information on the various L2 cache modules for Power Macintoshes and clones. While at a quick glance many of these L2 cache DIMMs look similar there are different pin (edge connector) groupings that key the 160 pin connector for different types of PPC Macs.
This is a work in progress, if you have any info to add or can check, take pictures of the modules in your Macs and let me know it would be greatly appreciated.
A - 6100/7100/8100
160 pin Cache DIMM
Pin groupings: 30 - 25 - 25
The first Power Macs have two identical ROM/L2 Cache DIMM slots on their logic boards. One of the two must have an Apple ROM DIMM. Apple included a 256KB cache DIMM with some models, and 1MB with the WGS 9150/120. Third party 512KB and 1MB modules were also made.
From @Ron's Computer Videos:
256KB - ? - Motorola, 5 chips ?
256KB - ? - IDT 7MP6080 ?
256KB - Micromac
1MB - Micromac
B - 6200/6300
160 pin Cache/ROM DIMM
Pin groupings: 30 - 25 - 25
The first, purpose built, PPC 603 Performas/LCs (5200/5300/6200/6300), have a combined ROM/L2 Cache DIMM slot on their logic boards. Since the ROM was on this DIMM only Apple made these special combo ROM/L2 Cache DIMMs. I don't believe a DIMM lacking L2 cache was made by Apple, i.e. all these Macs came with 256KB cache.
The last models 6320? may have ROMs on the logic board with cache only L2 Cache DIMMs. Need someone to confirm that though.
Note: The 6360 is the sole member of the 63xx Performas that does NOT use this type of L2 cache. It uses the modules under Section C below.
Note 1 - This is the Apple “REA” replacement P/N for bad modules
https://web.archive.org/web/20030203122255/http://docs.info.apple.com/article.html?artnum=20059
C - 4400/6360/6400/6500/TAM
160 pin Cache DIMM
Pin groupings: 35 - 25 - 20
I believe these should work in any Alchemy (6360/5400/6400), Gazelle (5500/6500/TAM) or Tanzania (4400/Clones) motherboard.
Note 1 - Umax Supermac c500/180 will lock up at boot with 512KB IDT7MPV6284 module. Also @François notes: Power Mac 6400 chimes but doesn’t boot, no video and the power LED doesn’t even light up! With this additional data point perhaps this module doesn't work in Alchemy based systems?
Note 2 - Confirmed to work in TAM
Pictures:
D - 7200/7300/7500/7600/8500/8600
160 pin Cache DIMM
Pin groupings: 25 - 35 - 20
I believe these should work in any Catalyst, Nitro or Tsunami based motherboard that has an L2 cache slot.
Note 1 - On Power Macintosh 7500/100 systems only, check the cache DIMM. If cache DIMM has part number 820-0719-B printed on its PCB, remove DIMM and replace with part number 661-1310.
Note 2 - Unclear if it actually presents as 288KB as the cache chip specs would indicate. The owner has not yet tested it, chance its not for Macs at all...
Pictures:
This is a work in progress, if you have any info to add or can check, take pictures of the modules in your Macs and let me know it would be greatly appreciated.
A - 6100/7100/8100
160 pin Cache DIMM
Pin groupings: 30 - 25 - 25
The first Power Macs have two identical ROM/L2 Cache DIMM slots on their logic boards. One of the two must have an Apple ROM DIMM. Apple included a 256KB cache DIMM with some models, and 1MB with the WGS 9150/120. Third party 512KB and 1MB modules were also made.
From @Ron's Computer Videos:
The MicroMac upgrade page for 1st generation Power Macintosh cache upgrades is still active: https://www.micromac.com/products/l2ca256k-6100.html
My understanding is that the main benefit of having the 1MB cache module is that the machine will move its VRAM use from DRAM over to the much faster cache module... thus increasing video performance by several times without having to sacrifice your PDS slot to a video card.
256KB - ? - Motorola, 5 chips ?
256KB - ? - IDT 7MP6080 ?
256KB - Micromac
1MB - Micromac
| Size | Apple P/N | PCB label | Sticker label | Cache Chips | Macs seen in | Notes | |
| A01 | 256KB | ? | ? | ? | ? | PM 8100/80 | |
| A02 | 256KB | ? | Apple Computer, Inc. 256K Cache SIMM | CYM9233PM 9509706 For use on 6100 only | 8 x Cypress Semiconductor CY7C193-22VC | PM 6100/66 | |
| A03 | 256KB | ? | 9406 REV B | SCM72MA32SG14 ATATZH9427 | 8 x Motorola MCM62940AFN14 | PM 6100/66 | |
| A04 | 256KB | ? | IDT 7MPV6080-01 | IDT7MP6480 | 8 x IDT 71256 SA15Y | PM 7100/80 | |
| Front | Back | |
| A01 | ? | ? |
| A02 | ||
| A03 | ||
| A04 | ||
B - 6200/6300
160 pin Cache/ROM DIMM
Pin groupings: 30 - 25 - 25
The first, purpose built, PPC 603 Performas/LCs (5200/5300/6200/6300), have a combined ROM/L2 Cache DIMM slot on their logic boards. Since the ROM was on this DIMM only Apple made these special combo ROM/L2 Cache DIMMs. I don't believe a DIMM lacking L2 cache was made by Apple, i.e. all these Macs came with 256KB cache.
The last models 6320? may have ROMs on the logic board with cache only L2 Cache DIMMs. Need someone to confirm that though.
Note: The 6360 is the sole member of the 63xx Performas that does NOT use this type of L2 cache. It uses the modules under Section C below.
| Size | Apple P/N | PCB label | Sticker label | Cache Chips | Macs seen in | Notes | |
| B01 | 256KB | 661-1278 | ? | ? | ? | PF 6320, 6320CD | 1 |
| B02 | 256KB | ? | ? | Samsung KMM864544G-12 Apple333-1087 | 8 x SEC KM68257CJ-15 | PF 6205CD | |
| B03 | 256KB | ? | 820-0672-A (1995) | SCP6AE32SG15 | 8 x Motorola MCM6206DJ12 | PF 6300CD | |
| B04 | 256KB | ? | 820-0672-A (1995) | IDT7MP6222 | 8 x IDT 71256 SA15Y | PF 6215CD |
Note 1 - This is the Apple “REA” replacement P/N for bad modules
https://web.archive.org/web/20030203122255/http://docs.info.apple.com/article.html?artnum=20059
| Front | Back | |
| B01 | ? | ? |
| B02 | ||
| B03 | ||
| B04 |
C - 4400/6360/6400/6500/TAM
160 pin Cache DIMM
Pin groupings: 35 - 25 - 20
I believe these should work in any Alchemy (6360/5400/6400), Gazelle (5500/6500/TAM) or Tanzania (4400/Clones) motherboard.
| Size | Apple P/N | PCB label | Sticker label | Cache Chips | Macs seen in | Notes | |
| C01 | 256KB | ? | IDT 7MPV6071 REV04 | IDT7MPV6071 | 8 x IDT 71256 SA15Y | ||
| C02 | 256KB | N/A | IDT 7MPV6071A-00 | IDT7MPV6071 | 8 x IDT 71256 SA15Y | Umax c500/180, Motorola StarMax | 2 |
| C03 | 256KB | ? | IDT 7MPV6283-01 | IDT7MPV6283 | 2 x IDT 71V433 S11PF | PM 4400/200 | |
| C04 | 256KB | ? | IDT 7MPV6283-02 | IDT7MPV6283 | 2 x IDT 71V433 S11PF | PM 6500/225 | |
| C21 | 512KB | ? | IDT7MPV6076 | 16 x IDT 71256 ? | Motorola StarMax | ||
| C22 | 512KB | ? | N/A | IDT7MPV6284 | 4 x IDT 71V433 S11PF | PM 6500/275 | 1 |
| C23 | 512KB | ? | N/A | IDT7MPV6289 | 4 x IDT 71V433 S11PF | ||
| C24 | 1MB | ? | IDT 7MPV6290 S50M 9813AA | IDT7MPV6290 | ? | After market, works in PM 6500/275 | |
Note 1 - Umax Supermac c500/180 will lock up at boot with 512KB IDT7MPV6284 module. Also @François notes: Power Mac 6400 chimes but doesn’t boot, no video and the power LED doesn’t even light up! With this additional data point perhaps this module doesn't work in Alchemy based systems?
Note 2 - Confirmed to work in TAM
Pictures:
| Front | Back | |
| C01 | ||
| C02 | ||
| C03 | ||
| C04 | ||
| C21 | ? | ? |
| C22 | ||
| C23 | ||
| C24 | ? | ? |
D - 7200/7300/7500/7600/8500/8600
160 pin Cache DIMM
Pin groupings: 25 - 35 - 20
I believe these should work in any Catalyst, Nitro or Tsunami based motherboard that has an L2 cache slot.
| Size | Apple P/N | PCB label | Sticker label | Cache Chips | Macs seen in | Notes | |
| D01 | 256KB | 661-1310 | ? | ? | PM 7500/100 | 1 | |
| D02 | 256KB | ? | 820-0585-A (1995) | SCP64MA32BSG11 ATATZA9613 | 4 x Motorola MCM67M518FN11 | ||
| D03 | 256KB | ? | 820-0719-B (1995) | 333-0178 MBAPS3330178D 9612 | 2 x Micron 58LC32K32B2LG-11 | PM 7600/132 | 1 |
| D04 | 256KB | ? | 820-0719-C (1995) 1172 B U.S.A 1896 | 333-0178 MBAPS3330178DP 9620D | 2 x Micron 58LC32K32B2LG-11 | PM 7300/200 | |
| D05 | 256KB | ? | 820-0719-C (1995) 1227 A U.S.A 2596 | 333-0178 MBAPS3330178DI 9633 | 2 x Micron 58LC32K32D7LG-7 | ||
| D06 | 256KB | ? | 820-0889-A (1996) | SCP64MD5DG9 QQAA9732 | 2 x Motorola MCM69F536BTQ9 | PM 8600 | |
| D07 | 288KB | ? | IDT 7MPV6302-00 | IDT 7MPV6302 | 2 x IDT 71V536 S10PF | 2 | |
| D21 | 512KB | N/A | 256K/512K CACHE | Advantage Memory Corporation | 4 x Sony CXK77V3211Q-12 | ||
| D41 | 1MB | N/A | LIFETIME MEMORY Mokini 10208 A | 1M CACHE DIMM Lifetime Memory | 8 x Micron 58LC32K32B2LG-10 | ||
Note 1 - On Power Macintosh 7500/100 systems only, check the cache DIMM. If cache DIMM has part number 820-0719-B printed on its PCB, remove DIMM and replace with part number 661-1310.
Note 2 - Unclear if it actually presents as 288KB as the cache chip specs would indicate. The owner has not yet tested it, chance its not for Macs at all...
Pictures:
| Front | Back | |
| D01 | ? | ? |
| D02 | ||
| D03 | ||
| D04 | ||
| D05 | ||
| D06 | ||
| D07 | ||
| D21 | ||
| D41 | ||
