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PM/WS 8500 needs AV module to boot?

belgaonkar

Well-known member
I recently purchased a Workgroup Server 8550 Prototype on eBay, when I received the machine the AV card was dangling outside the case and the cable was fed through expansion card slot. I tried removing the AV module as it was an eye-sore and I will never use it, but now it refuses to post. The machine powers up and does not display anything on screen. So does a Powermac/Workgroup Server 8500 series need an AV card to post? Or is this problem caused by the fact the machine has a Proto 604e 225MHZ logic board?

After It refused to post, I tried re-installing the AV card and ended up breaking the ribbon cable trying to hide the cable. Id like to know if the failure to post is caused by the AV module or Ive goofed something.

Side note: Ive ordered two AV cards, one for a 8500 series Powermac and another for a 7600 series Powermac. Under system profiler the machine identifies itself as a Powermac 7500/7600 series, so Im not sure which one the WS will prefer. 

 

Unknown_K

Well-known member
From what I recall the 8500 series just had a breakout panel (passive components) not a card for the A/V. Also the 8550 was just an 8500 with a tape backup drive in one of the drive bays plus some extra software.

Reseat the processor, hit the CUDA switch, and see if it boots.

 

belgaonkar

Well-known member
Tried that :(

think its the AV module as the previous owner tried to remove it and then realized it was necessary for the machine to post and crammed it back in. Ill report back once the the modules come in.

 

Bolle

Well-known member
You are not trying to boot the board outside of the case by any chance?

This is what I did when I got my 8500 and I had to learn that the board will not POST when it is outside of the case.

The metal shielding on the back of the case makes contact between the PSU frame and the ground/shield plane of the board. Without grounding the board that way it would not POST for me. I did not have the AV board plugged in back then if I remember right and it did work without it.

 

unity

Well-known member
^ Exactly, thats just an 8500. The only difference being maybe a bigger drive and server software on it. What makes it a proto? Im not seeing any signs. Stickers are for suckers we like to say. :) Whats the CPU card look like? The mobo part number?

 

belgaonkar

Well-known member
Heres a screen shot of system profiler. It sees the machine as a 7500 and claims it is a dual processor.

IMG_3111.JPG

 

360alaska

Well-known member
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unity

Well-known member
I wonder if its been modified? Its a stock run board, but makes one wonder. That EIGER label, I've not seen that before. But TNT is the code name for the 7500, but thats not a 7500 board from what I can tell which I think is 820-0564-A. But I am not 100% sure on that since the 76/7500 design is the same really. Either way, pretty cool find. I wonder what it is or what is was going to be. Any thoughts? Are the ROMS stock or in a SIMM with any label?

 
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MJ313

Well-known member
I took apart an 8550 and 7600 once and noticed that neither one had a VLSI chip. Out of curiosity, I wonder if your board has that chip. When I looked at 8500 boards online, they had the chip (the silkscreen on the board actually outlines the chip.. it's near the center of the board). The boards are all so similar though and the 8550 didn't ship with an A/V module anyway. I will guess that it really is exactly what the box says it is... an 8550... and a nice proto! 

Neat find regardless of what it is!

 
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unity

Well-known member
I sat down and put some thought into this and this is just a wild guess.

CPU code names:

Apple’s  first RISC project (based on the Motorola 88000 RISC): Jaguar, Tesseract
PowerPC 602: Galahad
PowerPC 603: Wart (King Arthur’s trusty aide) PowerPC 603e/603+/603ev: Stretch, Valiant PowerPC 603et: Goldeneye
PowerPC 604: Zephyr
PowerPC 604e: Helm Wind, Sirocco, Twister PowerPC 604eq: Mach 5

Mac code names:
Power Mac 8600 and 9600: Kansas, Montana
according to:
https://doc.lagout.org/science/0_Computer%20Science/Apple%20Confidential%202.0%20The%20Definitive%20History%20of%20the%20World%27s%20Most%20Colorful%20Company.pdf

Mac code name:
Montana – Macintosh Classic IIMontana – Power Macintosh 7300
Montana 7600 – Power Macintosh 7600
According to:
https://en.wikipedia.org/wiki/List_of_Apple_codenames
^ I tend to trust Apple Confidential more than Wiki.
The case its in might be irrelevant.

Your machine ID: 68 = 7600, 7500  (Machine ID for 8500/8550 is 69)
Your case is physically dated: January 1996
Your CD drive is from: May 1996
Your CPU card is from roughly March 1996.
Your motherboard is from 1995.

So yours might have been put together in early 1996.

The 8500/8550 came out in late 1995. I think this rules out an 85XX proto unless they were planning really far ahead. Even then, why not use a motherboard from an 85XX series?
7600 came out in April 1996 = Could be 7600 proto. It originally had 604, but for a short bit did get a 200Mhz 604e. Could a dual 604e been planned ahead? I sorta doubt it and why the tower case? And this machine would have been put together just as the machine was released. Timing is not right.

9600 debut: Febr 1997 = Given that development time can take years and the dual CPUs did come out day one for the 9600...

Note: The machine ID of the 9600 is 67, the 8600 103 - even though they came out at the same time. Implies the 9600 was in development longer maybe? (Machine IDs are not always sequential) 8600 did not have dual CPU, 9600 did. Also the 9500 ID is 67 which is older of course. Why did Apple carry this ID over? The motherboard of the 9600 is very different than the 76/7500 or for that matter the 85XX but very similar to the 9500.

My conclusion, which is very much to be taken with a grain of salt:

The 9500, which debuted in May 1995 and was code named Tsunami, got dual 604e processor upgrades later in August of 1996 @ 180Mhz. So my guess is this machine was either a test bed for dual CPUs that ended up in the 9500 or its a very early concept for a 9600. Or both. Keep in mine during this same time, the Manhattan/PowerExpress Manhattan project was going on. Those would be G3 projects. So development was going in 100 different directions. As for the code name Montana, I am sure that by the time this dual card was made, Montana (9600) was well into planning and development. It would be out in about a year but I bet no main logic board was finalized, but dual CPUs - probably green lit and planned. So Apple probably started developing dual CPU cards/software as part of the planning for the 9600 and for software developers to get early setups to develop on. And I bet this is why the 9500 also got dual CPUs late in the game, granted at a "reduced speed" as to not compete with the soon to be released 9600, but still to keep Apple ahead of the competition and sales revenue. Probably a push from marketing. Not to mention Apple could finally say they have a dual CPU system. That also means, unless I am forgetting something, this may be one of the very first dual processor setups Apple made! In early 1996, no dual processor setup was sold by Apple yet.


 
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belgaonkar

Well-known member
Oh wow. I really gotta get this thing to post now. A new AV module has been ordered. Ill also buy a donor 8500 to make sure the body is pristine. If its truly the first dual processor machine Apple has made, it deserves new plastic!

Anyone want to sell a Powermac 8550 or WS 8550?

 
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MJ313

Well-known member
I'm loving unity's explanation. it's so good in fact, i've changed my mind on my guess... :D That cpu in there... unicorn!  

 
 

belgaonkar

Well-known member
Got the AV module for a 7600 today. No success. The manual suggest resetting the Cuda Chip which has also been done. I have a feeling its going to be an issue with the power supply grounding on the case. I tried reassembling the case and booting it up, but nothing happens. 

 
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