Tsunami vs. Kansas logic boards (PM9600)

[Schmoburger]

So, after reading trag's contribution to a thread involving CPU card compatibility in edge-slot Powermacs, I note that there are actually fairly significant differences between the Tsunami and later Kansas boards in the 9600... In any case, I decided to pull out my spare 9600 board to identify it and discovered it is actually a Kansas unit. My 9600, being a 200MP, is the earlier Tsunami architecture. Now this for one, explains why it wouldnt operate with the 200MP card in the spare board.

Anyway, as it stands, I currently run the 9600 in a heavily upgraded form with a Sonnet G3/400 CPU, 768Mb of RAM interleaved, an aftermarket bootable wide SCSI card, 3 hard drives, CD-R drive, a Targa2000, firewire and USB cards and a later 8Mb TT128 video card. Once I get hold of some more gear I will be using  it occasionally to do some video and sound work just for funzies, as well as being my support machine for all the old gear. The question I have is, is there any benefit to having one board over the other... I am aware that if I ever want to revert to the stock dual-604e config, I will need to use the original board. But in the current configuration, is there any benefit (or vice) to using the Kansas board?

 

[TheWhiteFalcon]

I think that the Kansas board fixed some issues that had crept up in the Tsunami architecture?

 

[604ev]

In the current configuration, is there any benefit (or vice) to using the Kansas board?

As a benefit, the Kansas board has support for Speculative Access.

 

[AichEss]

How do you know which board you have?

 

[trag]

As a benefit, the Kansas board has support for Speculative Access.

Which, according to reports, back when, only gains one a few percent performance. Also, it only applies when using a G3 processor. Still it's some improvement. However, there was also a report that PCI performance was lower on the Kansas boards. At this late date I'm not sure I'd trust either report without some carefully controlled test comparisons.
One thing to remember is that Tsunami and Kansas are not *different* architectures. They are very slightly different implementations of the same "Power Surge" architecture. They use the same Hammerhead bus arbiter/memory controller chip on the CPU bus, the same pair of memory data controller chips ( slightly different on the ANS with its support for parity memory), the same PCI bridge chips (bandit), the same interrupt handler (grand central), and all the same peripheral chips which provide SCSI, Ethernet, serial port, etc..

How do you know which board you have?

The only hardware differences Kansas boards have is a lack of on-board CPU cache (9600) or cache socket (8600), because the cache was moved to the Mach V CPU card; different ROM version, revision numbers I don't remember but they're in my referenced post, but part numbers on the four ROM chips are 341S0280 through 341S0283 (original) vs. 341S0380 through 341S0383 on the Kansas boards; and some slight wiring differences in the CPU socket which I think are just an expansion of the number of 3.3V pins, but I never traced it out in enough detail to be willing to say with certainty.
Replacing some of the 12V or 5V pins with 3.3V would be plenty to make the CPU card's not compatible, yet be fairly easy for 3rd party upgrade makers to adapt around.

If one takes a set of Kansas ROM chips off of a Kansas board (or programs the contents into 44 pin PSOP Flash chips, e.g.) the Kansas ROM can be installed in all earlier x500 and x600 machines and clones and they work fine. Strangely it also works just fine on the 7200 and Catalyst clones but not that strange given that the Catalyst systems use the same ROM as the early x500 machines.

 

[Gil]

I wasn't aware that Tsunami boards were used in 9600s. Wasn't that the architecture for the 9500?

 

[trag]

I wasn't aware that Tsunami boards were used in 9600s. Wasn't that the architecture for the 9500?

9500 and original non-Kansas 9600 are identical except for different power supply connector and different ROM revision (341S0168 through 341S0171 vs. 341S0280 through 341S0283). On a few very early 9500s the ROM chips are 341S0106 through 341S0109 instead of 168 - 171.
Original 9600 and "9600 Enhanced" (Apple's name for the Kansas machine) have only differences noted in previous post. Difference between 9500 and Kansas 9600 is therefore only power supply connector, removal of logic board cache, different ROM revision, and slight wiring difference ( more 3.3V pins?) in CPU socket. Oh, and different case, but that's not a logic board difference. And, obviously, they originally shipped with different CPU card's, hard drive options, and memory, but again not a logic board difference.

Did all three ship with the Apple branded Twin Turbo as the video card? I think the 9500 shipped with something earlier because the enabler for Apple's version of the TT has "9600" in the name.