For Sale: PowerExpress Motherboard

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Hawaii Cruiser's picture
Last seen: 1 year 4 months ago
Joined: Jan 20 2005 - 16:03
For Sale: PowerExpress Motherboard

I have placed my now-famous Apple Macintosh PowerExpress (Powermac 9700) motherboard up for auction on eBay here:

PowerExpress motherboard eBay auction

The auction starts on October 5, 2008 at 6:45pm Pacific Daylight Time, and ends on Sunday October 12, 2008 at 6.45 Pacific Daylight Time (probably just at the moment the wish is made and the candles are being blown out at my daughter's birthday party).

This is the same motherboard that we discussed at great length in my first thread years ago here: "POWEREXPRESS REVISITED"

and continued recently here: "POWEREXPRESS REVISITED PART II"

The PowerExpress, (and its desktop cousin, the PowerExpress Manhattan) was to be the Powermac 9700, the successor to the Powermac 9600. The PowerExpress was a much more powerful motherboard that fit into the exact same case as the 8600 and the 9600. Development had arrived to the month when production was to begin, but this was also the moment that Steve Jobs returned to run Apple, and Steve had a different vision and different ideas--which had a lot to do not only with technology, but also with earnings and marketing. Even though it was right on the eve of production, Steve canned the PowerExpress in order to highlight his new, and in some ways faster, although smaller and less featured, Powermac G3 (the PowerExpress was acually designed to incorporate either the new G3 processor or a dual 604e processor). There are only a few survivors of these motherboards left, and mine is one of the very rare ones that has ROM chips.

Was canning the PowerExpress ("PEX") the best decision? Well, you decide:

Steve's favored G3 (nowadays called the "Beige G3") had only three PCI slots along with onboard video. The PowerExpress has--like the 9600--six PCI slots along with onboard video--and the onboard video system also included a new slot on the motherboard--a new technology--the "VCI" slot for exchangeable video processing daughter cards. That's the VCI slot behind the processor slot.

The Beige G3 relied on an ATA/EIDE bus for its hard drive and CD drive, doing the standard EIDE/ATA 16mbs for that time. Its internal SCSI bus was downgraded from the standard 10mbs to 5mbs, and the 50 pin internal SCSI was actually not utilized, nor was it intended to be utilized, in any way in the system. This was the moment when Apple, through Steve's leadership, chose to abandon internal self-processing SCSI for the cheaper priced, and many will profess, slower in many ways, main processor reliant ATA/EIDE.

Look at the assortment of buses on the PowerExpress up there in the top left corner. Like the G3, it had two ATA bus slots, and an internal 50 pin SCSI slot. But look what's between them--a 68 pin fast Ultra SCSI slot (40mbs?)!!!--and next to them all, the previously standard 5mbs DB25 SCSI external port has been replaced with a fast 68 pin SCSI mesh connector. This was a motherboard designed for a very fast SCSI setup which would have blown away ATA/EIDE. The ATA slots were probably for the optical drives and an option, if you found some need for cheap and 16mbs-slow ATA hard drives.

Like the 9600, the PowerExpress has twelve 168pin DRAM memory slots. The DRAM which the PEX uses is 3.3v DRAM, not 5v which is the Apple standard (only the PM 4400 and some of the Mac clones used 3.3v). I have installed--interleaved--384mb of 3.3v DRAM which is included in the auction.

Also of interest on the motherboard, the floppy connector is the PC floppy style connector, larger than the standard Apple connector, and there is an internal AV connector behind the external audio jacks for an AV module--just as there is an AV connector in the same place on the 8600 motherboard, although the PEX connector is smaller than the 8600's.

So you see, the PowerExpress is a mega, maxed-out motherboard, probably the most complex Apple ever made, with much more capabilities than the 9600, and has many more options than the Beige G3. Granted, the Beige G3 had a platform that well outpaced the PowerExpress's I/O chips, but the expansion capabilities, the addition of fast SCSI on top of EIDE, as well as the promising VCI technology concept seem like quite a loss next to The Beige G3's trim, smaller package. Even after the production of the Beige G3 was well underway, production of the 9600 was renewed because of consumer preference for the much more expandable 9600 over the Beige G3.

The form factor of the PEX motherboard is exactly the same as the 9600/8600 form factor, so it sits snugly in the 8600 or 9600 case (they are the same case). There are only a couple small differences, though. The 9600 and 8600 motherboards are secured into place, besides by the plastic clips, by one screw in the middle of the motherboard next to the inmost DRAM slot. The PEX motherboard does not have a hole for this screw and is held into place only by the plastic clips--which suffice for the purpose. I put a piece of electrician's tape over that one screw's metal connector on my 9600 case just to make sure the PEX motherboard is protected from possible damage by the lone screw connector (probably overprotective, but why not?).

The other difference from the 9600 is the PEX, unlike the 9600, but like the 8600, has an onboard video connector, so the video connector opening on a 9600's back plate has to be punched out to accommodate the PEX's video port. The video port is in the exact same place as the 8600's, and since the 9600 uses the same case, the plastic on the 9600's back plate is already stamp-cut so that the port hole can be easily punched out.

The other difference with the back plate is the PEX's mesh 68pin external port is slightly larger than the 9600/8600's DB25 port and requires some slight trimming of the plastic of the SCSI port hole to accommodate the PEX's SCSI port.

But alas, since the PowerExpress never went to production, and most of the prototypes were destroyed, only a few prototypes have survived, which is what mine is. And also alas, mine does not boot to a Mac OS, nor to a system installation disk. It does chime ( a VERY unique, comical voice "chime" ) but no video output comes up on its own. There is no record that I know of that any of the other few existing PEX motherboards boot to OS (although one participant in the PEX Revisited thread claimed that while working he was working at Apple technicians were actually using PEX's to perform tasks in their labs). My motherboard, among all the survivors, is apparently very rare in that it has two ROM chips in place. Most of the others have no ROM chips. Mine does boot to Open Firmware (OF) via a serial connection to another Mac. Using OF, both the onboard video and a PCI video card can output a video signal to a monitor. Since OS 9 is reliant on ROM, and my PEX's ROM seems to not be able to boot, OS 9 may never boot off this motherboard (unless, of course, some superwiz can come up with a working ROM card--the motherboard does have a ROM slot and I will also include a Beige G3 ROM card if someone is capable of that challenge).

The exciting development is, though, there seems to be a very good possibility that OS X could boot by bypassing the ROM, and by using Open Firmware and a hard drive with a previously XpostFacto-installed OS X (made on another Powersurge Powermac). I have been able to bring up OS X's BOOTX on the PEX, including the gray apple on the video screen, from a burned copy on a CD. These attempts at boot are well documented online on the thread I linked to above.

As you'll see I was very naive with my new possession back then and was guided through the exploration of my PEX by very skilled and experienced Mac experts here--a project which became well-watched and caused great interest at this greatly-visited, popular website devoted to Apple computer topics.

What is the value of this Macintosh historical artifact? Well, consider its significance. It was a topic of pivotal concern during one of Apple's greatest transitional moments. It has the wrath of Steve Jobs plastered on it. It is the antithesis of Apple's decision to limit onboard expandability, and thereby represents in some ways, the conclusion of an age. And it also represents what could have been, and perhaps what should have been. It is also very rare because most other prototypes were destroyed and even more rare because of its onboard ROM. And quite simply, it is also a marvel of complexity and a work of technological beauty designed by committed engineering artists.

I hope it ends up with someone who truly appreciates its value.


dvsjr's picture
Last seen: 1 year 6 months ago
Joined: Jun 8 2004 - 15:14

Holy crap.

eeun's picture
Last seen: 6 days 16 hours ago
Joined: Dec 19 2003 - 17:34
No, really...this thread is s

No, really...this thread is soley for the purpose of selling this board.
Please follow HC's request and post any comments or observations here: "POWEREXPRESS REVISITED PART II"

Hawaii Cruiser's picture
Last seen: 1 year 4 months ago
Joined: Jan 20 2005 - 16:03

I've just added a copy of DiskWarrior and a DVD-RAM drive to my list of items for sale at eBay. My PEX auction is open to buyers worldwide. My other auctions all say no international sales, but anyone I'm familiar with here at Applefritter is welcome to bid on the other auctions. If you are out of the U.S., just use the personal message here at AF to inform me of your eBay user name to let me know who you are.

It looks like the BSA has, once-and-for-all, successfully tyrannized the Apple OS eBay auction categories. My X Public Beta and my 10.1.3 installation disks auctions were both pulled by eBay (with no notice to me!). I guess you won't be seeing anymore gray installation disks on eBay. Yeah, I know...EULA. I just missed it, it seems. I saw them selling very well just a week or so ago.

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