PowerExpress Revisited

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DigiBarn PowerExpress

I believe it is a G3 for several reasons. First, the processor card is different from both the regular Apple 604e card and the Mach 5 version, both of which I have. Secondly, several years ago an anonymous contributor sent to AppleFritter pictures of a PowerExpress along with information about it. That person said the PowerExpress was going to have three configurations. One would be a single 350MHz 604e, another would be a dual 350MHz 604e, and the third configuration would be a 275MHz G3. Therefore, DigiBarn's PowerExpress likely has the 275MHz G3 configuration. Also, the fact that the processor card says on it "Motorola Engineering Sample" would indicate that this processor card is not the same one Apple was already shipping in Power Mac 9600s at the time. In September of 1997, the PowerPC 750 was a brand new chip and is likely why that processor card was made specifically by Motorola.

That isn't a cache card, it is a ROM card. Notice on the lower-left corner of this picture here that the slot is labelled "ROM". These motherboards have no provisions for a cache card. This ROM card probably contains the Mac OS Toolbox, which is needed to load the classic Mac OS.

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Very Cool!

Wow! I'm salivating over that ROM card!

If that's a G3 processor, would it need a special system extension to enable it, or would that function be built into the ROM? Also, is the .5GB of RAM 3.3V? Very strange that it's got all the onboard VRAM and video chipsets and no monitor port. I believe it was mentioned earlier that this is one of the 50 production models, and the only one that survived, but the missing monitor port would suggest it's still a prototype, wouldn't it?

That ROM card is the most valuable piece of hardware in the PEx universe, if it actually belongs there. It's the only known example in existence.

I wonder why someone bothered to mount a harddrive on the bottom of the case?

I do have a Mach 5 350mhz CPU which I tried early on. I can't remember, I think I may have gotten the chime with it installed.

Sorry for my last long diversion about my B&W troubles. The B&W motherboard did come back to life a couple of days later as if nothing had gone wrong at all. I suspected it would. Motherboards are so funny that way. But I'm still using my 9600 and enjoying it and using the B&W somewhere else. I've been keeping my eye out for a local 9600 or 8600 case in order to resurrect the great adventure, but nothing has turned up yet. One will turn up sooner or later. If we do continue on, we should probably create a PowerExpress Revisited Part II thread. This ones getting pretty long.

Are these DigiBarn people Mac specialists?

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Re: Very Cool!

If that's a G3 processor, would it need a special system extension to enable it, or would that function be built into the ROM?

That function would probably be built into the ROM. The original (Kanga) PowerBook G3s were able to run 7.6 and IIRC they didn't need any special system extension for the G3.

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G3, I'd guess

I would guess it's a G3 CPU rather than a 604e. The reasion I say this is that the clockspeed is 275MHz. At the time, the Mach 5 604e's were clocked at 250, 300 and 350MHz, while the first G3's were arriving clocked at 275MHz - remember those never-released PCC and Motorola clone prototype G3 machines? They were both running at 275MHz.

Now, Apple could have simply chosen an intermediate clock multiplier for PEx, running at Mach 5 604e at the in-between speed of 275MHz. But it seems more likely given the above facts that it's indeed a G3 in that Digibarn prototype - with a 604e-style and sized heatsink.

Matt

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VCI

In case it hasnt already been mentioned, VCI is a simple spin of PCI, and means Video Component Interface.

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VCI

Wow, nice to see people are still interested in my old thread here.

So does anyone know if any other computers had VCI slots and if there were any VCI cards ever produced and marketed? Doesn't sound like it. Sounds like it was an idea canned along with the PowerExpress.

In case anyone's curious, I picked up a PM 8600 months ago, but the house is a mess, and I've not mustered the time and energy to rig up the PowerExpress again yet. The motherboard is sitting safely and snugly in a box on the shelf awaiting that day. I've been watching the OS X Beta auctions and hope I can snatch one up cheaply before that.

I wonder what ever happened to DigiBarn's attempts at a boot on their machine? Seemed like a sure thing waiting to happen. He just needed a later OS or something like that.

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Definitely

Macs with PowerPC Processors wont accept an OS earlier than 7.5, and by the age and year
of the Digibarn PEx I would say it needs OS 8 at least.

Anyway, I find this thread very interesting, shame AF let it die out at this point. Just as it
started getting good too.

Anyway, i'm looking for an image of the old PEx rom (it's here somewhere), if I do find it,
i'll run it in to SheepShaver and boot OS 8 on it. I know it can be done, someone managed
to get it to work once.

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Not True...

The first generation Power Macs (6100, 7100, 8100) shipped with system 7.1.2.

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Ah.

Well, the PEx wouldnt be able to run 7.1.1 anyway. It ceased support with some PPC
models.

jt
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I'm still interested too . . .

. . . I just haven't had time to look up some old info. A couple of years ago, an engineer at one of the G4 accelerator manufacturers gave me a 90% probability of getting my board up and running using a specific card/adapter combo. This estimate was based upon my success in getting the boot chimes to sound consistently in one of my test configurations. Considering the 30 day money back gurantee, it still sounds like a good avenue to pursue, when I have the extra $ to throw at the project just in case it actually does work!

My guess at the reason for his optimism is that ROM on the accelerator would instruct the CPU to poll the I/O bus for system software A/O accelerator drivers immediately after the startup test was passed. I'm hoping that my PEx board isn't hanging at too low a level in the boot process for an accelerator to give it a kick in the pants.

Whatcha think of that notion, gang?

jt/Trash80toG-4

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Accelleration...

The fact the PEx is chiming probably tells that it has the power to access the processor.
Dropping an upgrade card in there will likely do it some good, especially if it has On Card
ROMS.

I say, when I find the cash, go for it. 90% probably aren't bad odds.

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OS X Beta or ...

i have a mac os x server 1.2 original cd that works natively with old world macs, like the os x beta.

do you think it would do the thing?

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What does works natively with

What does works natively with old world macs mean? Does 10.1 add support for anything pre-G3?

I was thinking about waxing up the old PEX board and taking it out for a session again (but I've thought that before, so...). I've got some ideas about what went wrong with the attempts at booting before. I screwed up the ROM on the Acard somehow, so I'm hoping to try a boot through the onboard SCSI instead. I've got a copy of OSX Beta which has a PEX kext file, but I think the Beta may be too problematic. If you could get a copy of that CD to me, it would be much appreciated. Personal message me and we can discuss compensation. My zip code is 96822.

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Dont Remember Specifics...

but I had a ... God, what was it, 7200? 7600? Running OS X, via XPostFacto. So, it's in there somewhere, but I don't think that is going to help much where you're at right now.

Maybe once/if you can get into and/or play in Open Firmware? Then you can issue the commands XPostFacto would have in order to get the disc booting.

(The Setup Assistant was quite the pain to get through/around at 640x480, couldnt move it much at all, couldnt tab thru buttons, couldnt use a Windows Alt+O of course... I think I might have force quit it and just gone from there.)

-- Macinjosh

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Re: PEx Manhattan Open Firmware Words and Public Beta


When attempting to boot the Public Beta installation CD, the partition you need to direct Open Firmware to is partition 9. The boot-path should be like this.
boot scsi-ext/@3:9

does open firmware also needs arguments for the bootloader partition Apple_Boot MOSX_OF3_Booter ?

here is the partition map from a macos x server 1.2 hd installed on a 9600/300:

/dev/rsd0h map block size=512
#: type name length base ( size )
1: Apple_partition_map Apple 63 @ 1
2: Apple_Driver43*Macintosh 54 @ 64
3: Apple_Driver43*Macintosh 74 @ 118
4: Apple_Driver_IOKit Macintosh 512 @ 192
5: Apple_Patches Patch Partition 512 @ 704
6: Apple_HFS Macintosh HD 2238137 @ 1216 ( 1.1G)
7: Apple_Boot MOSX_OF3_Booter 16384 @ 2239353 ( 8.0M)
8: Apple_Loader SecondaryLoader 1024 @ 2255737
9: Apple_Rhapsody_UFS Mac OS X Server 1.2 6210429 @ 2256761 ( 3.0G)
10: Apple_Free Extra 9 @ 8467190

would a pre-installed hd work better on the scsi mesh than the ufs+hfs install cd?

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