PowerMac 9600 Logic Boards

Could someone explain the difference between the two logic boards? One appears to have more soldered on chips near the PCI slots and one is missing them. Just curious on why they made two different versions..

Here are the two boards

Take care, the processor slot on the newer Kansas version was updated to take 604ev (Mach V) processor cards and is electrically different. Don't put an Apple Mach V card in a Tsunami 9600 logic board. I assume the same is true in reverse? But I don't know.

Other changes... off the top of my head, they moved the cache from the logic board onto the processor card, and deleted the ROM slot? Pads are still there. Not sure what else.

Sadly a Kansas board won't boot BeOS due to the differences.

aplmak said:

Here are the two boards

Click to expand...

The dark green one is Kansas.

I was wrong about the ROM slot, my Mach V 8600 doesn't have the slot.

A quirk is that some G3/G4 upgrades don't like the built in cache on the Tsunami boards, Sonnet and probably others made it that their upgrade card's cache would be used as L3 cache and the logic board as L2. Sadly this is slower, but at least it works. You can disable the onboard cache by either removing (I think) or adding a little resistor.

In a Kansas board the upgrades just work as normal with onboard L2 Cache on the upgrade card.

Went looking for the resistor mod and found a nice description of the two boards as well :

Phipli thanks for the info!! I actually don’t have a 9600 but was curious. I was considering one. This information I’m sure will be very helpful to someone with one. Which brings me to the PM8600.. I am about to pop into tomorrow a G3 upgrade. I have the Motorolla 604 @ 300 MHz. So it has the Rev. A with no cache on the logic board, the cache is built into the processor card. I hope it’s compatible.

My new processor is a Newer Tech Technology MAXpowr Apple G3 Processor DT351C2

I do have a Rev B with a cache slot, would it be better to avoid conflict and use that board??

aplmak said:

Phipli thanks for the info!! I actually don’t have a 9600 but was curious. I was considering one. This information I’m sure will be very helpful to someone with one. Which brings me to the PM8600.. I am about to pop into tomorrow a G3 upgrade. I have the Motorolla 604 @ 300 MHz. So it has the Rev. A with no cache on the logic board, the cache is built into the processor card. I hope it’s compatible.

My new processor is a Newer Tech Technology MAXpowr Apple G3 Processor DT351C2

I do have a Rev B with a cache slot, would it be better to avoid conflict and use that board??

Click to expand...

Careful, I suspect your "Rev A" sounds like the new style board as all 300mhz 604 chips are 604ev and your "Rev B" might be rev b of the older board type. The "rev" relates to the part number, and there are two 8600 board versions, like the 9600. Check the copyright year

The upgrade will work in either, but remove the Cache SIMM (not a ROM SIMM) before installing it if the machine has a cache SIMM.

The two boards I have are...
820-0858-B is the 604e board, with a cache slot, ©1996

820-0931-A is the newer 604ev board, with no cache slot, ©1997

The B and A are just revisions, and in this case, because the part numbers are different, chronologically backwards.

For reference :

Yes I have both of those. I have some spares as well if each. I’ve actually recapped them with tantalum capacitors before they eventually leak. I’m trying to get ahead of the game instead of having to clean up leaked cap boards that have damaged other components. You may want to consider doing this too. I’ll use the “ev” board for the new G3 upgrade.

Phipli said:

The dark green one is Kansas.

I was wrong about the ROM slot, my Mach V 8600 doesn't have the slot.

Click to expand...

Just for the record, its the cache slot missing on the late 8600, I just got myself muddled

I'm using a Sonnet 450mhz G3 card in a Kansas 9600. I know how parts stored away from computers get mislaid so I stashed the original in one of it's hard drive bays

That’s an excellent idea. All my bays are taken up. There is a huge amount of space at the bottom of the case though. I installed the G3 300mhz NewerTech MaxPowr and it works excellent. I set the dips to #1 & #4 on as recommended for the Mach 5. Installed the NewerTech MaxPowr software 2.0.5. What a difference in speed!!

There are three versions of the 9500/9600 board and three versions of the 8500/8600 board. Apple may have built more revisions, but there are three that matter to hobbyists.

PowerMac 8500, PowerMac 8600, PowerMac 8600 Enhanced (AKA Kansas)
PowerMac 9500, PowerMac 9600, PowerMac 9600 Enhanced (AKA Kansas)

There are several features that change with the changing versions:

1) 2 sets of Power supply connectors

8500 and 9500 have one version of power supply connector.

Both 8600s and 9600s have the other version.

I can't remember the details but it's something like 22 pin vs. 26 pin plus a rewiring of 12(?) pin connector.

2a) Cache slot

Present on the 8500 and 8600. MIssing on the 8600 Enhanced.

2b) On-board 512K Cache chips

Present on the 9500 and 9600. MIssing on the 9600 Enhanced. (these are the chips in front of the PCI slots mentioned by the OP).

3) ROM chips

These are four chips numbered consecutively. They are 44 pin PSOP chips, flat surface mount chips with 22 pins down each long edge. Dimensions of about 1.1" X .5". On the 8x00 boards these chips are on the underside of the board.

8500, 9500 Chips labeled 341S0169 - 341S0173 (Note a few rare boards with 341S0106 - 341S0109)
8600, 9600 Chips labeled 341S0280 - 341S0283
8600 Enhanced, 9600 Enhanced Chips labeled 341S0380 - 341S0383

4) ROM revision in Apple System Profiler

8500, 9500 $77D.28F2
8600, 9600 $77D.34F2
8600 Enhanced, 9600 Enhanced $77D.34F5

5) CPU Slot

The physical CPU slot is identical in all models.

8500, 9500, 8600, 9600 Electrically the CPU slot is the same for all these models. These support the Apple CPU cards, except the Mach V cards.

8600 Enhanced, 9600 Enhanced Electrically, the CPU slot only supports the Mach V CPU cards and 3rd party upgrades that support Kansas/Mach V.

Mach V cards are Apple CPU cards with PPC604E at the speed of 250 MHz or higher. Note there were a few rare 3rd party CPU cards with PPC604E at 250 MHz. These 3rd party cards were not Mach V cards.

trag said:

Mach V cards are Apple CPU cards with PPC604E at the speed of 250 MHz or higher.

Click to expand...

AFAIK, Mach 5 ist not 604e, it‘s 604ev or mostly called 604r, ranging from 250Mhz up to 400Mhz. Everything 300Mhz or higher is only suited for Kansas (inline cache) units. This 100Mhz Inline Cache was possible as the 604r supported a bus speed of of up to 100Mhz - compared to max. 66Mhz for the 604e. Back in the 90s, I was working on a 400Mhz 604r card for the regular non-enhanced 8x00/9x00 and 7500/7300/7600. It wasn‘t a big success as the 750was already available ins small quantities. Only super heavy number crunchers had a benefit from the 400Mhz 604r with its much advanced FPU compared to the 750.

I've never seen 604r used in a public-facing Mac context, is that something IBM used for 604-based AIX machines, or was it the name of a further evolution of the 604 design that would have succeeded 604ev?

If so, we should probably continue using the terminology Apple and all of the Mac books, magazines, and sites have been using: 604ev. It's also not in NXP's datasheet, and wikipedia's mention of 604r isn't, itself, cited or explained.

Coloruser said:

Only super heavy number crunchers had a benefit from the 400Mhz 604r with its much advanced FPU compared to the 750.

Click to expand...

It would have been interesting to see that. Apple did have a /233 card for those machines and I think maybe NewerTech had a, like, /250 or so that matched the 250 or 275MHz card UMAX and PowerC were using, but I don't have refs on hand for those.

In my own testing, 604ev@300 and G3@300 are the same speed at floating point and the G3 is twice as fast at integer work (which is most of what people notice day-to-day in Classic Mac OS.)

Cory5412 said:

In my own testing, 604ev@300 and G3@300 are the same speed at floating point and the G3 is twice as fast at integer work (which is most of what people notice day-to-day in Classic Mac OS.)

Click to expand...

Are there 604 specific compiler flags? It feels like the sort of thing software would need to specifically take advantage of. Or at least the mac maths libs.

Although that would be a bottomless pit of testing.

Cory5412 said:

I've never seen 604r used in a public-facing Mac context, is that something IBM used for 604-based AIX machines, or was it the name of a further evolution of the 604 design that would have succeeded 604ev?

If so, we should probably continue using the terminology Apple and all of the Mac books, magazines, and sites have been using: 604ev. It's also not in NXP's datasheet, and wikipedia's mention of 604r isn't, itself, cited or explained.


It would have been interesting to see that. Apple did have a /233 card for those machines and I think maybe NewerTech had a, like, /250 or so that matched the 250 or 275MHz card UMAX and PowerC were using, but I don't have refs on hand for those.

In my own testing, 604ev@300 and G3@300 are the same speed at floating point and the G3 is twice as fast at integer work (which is most of what people notice day-to-day in Classic Mac OS.)

Click to expand...

AFAIK, 604r was what IBM called it internally. The chips were labelled 604ev. Regarding the FPU, the floating point of the 603 and G3 had only a 32 bit multiplier (ALU) -- so for floating point multiplies it took two passes (2 cycles) to do a 64 bit floating point operations. The 604's had a full 64 bit multiplier, and so did better at floating point math performance than the others (up to twice as fast). The G4 has picked up the 64 bit ALU, so the G4 does have better floating point performance than the G3.....

Coloruser said:

AFAIK, Mach 5 ist not 604e, it‘s 604ev or mostly called 604r

Click to expand...

Useful tidbits, but my goal was to make it easy for folks to identify. If you find an Apple PPC604e card set for 250MHz or faster, then it is a Mach V card as they did not make any other PPC604e cards at those speeds. Yes, the processor is actually a 604ev or 604r, but the user isn't going to know that unless they pull hte heat sink off the processor card.