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NuBus Processor Upgrade Hardware revamp?

I've been puttering around with my Powermac 7100/66 and while they're a steadfast beast, it's a bit on the slow side.

After finding a couple of PDS-mounted processor upgrades on eBay, I've kinda noticed that you can find the processor upgrade cards but never the chassis and flat flex cabling for connecting a PDS video card.

I found myself wondering about whether anyone's tried reverse engineering the flat flex cables and built a 3d printed chassis.

Also, I put out a request to both Sonnet and Newer Technology if they have a BOM/Schematic we could use to do something like get PCBWays to print them. I know the connectors are probably rare but just having the hard bits done might help things along.

Am I tilting at windmills? A giant caveat is that I'm no electrical scientician.

Also, anyone out there have any of these upgrades that would be willing to provide dimensions/photos?
 
Got a response back from Sonnet saying that they don't have the schematics for the flat flex and case for the Sonnet AV/HPV Card Video Adapter Kit. Haven't heard anything from Newer Tech.
 

ArmorAlley

Well-known member
I've been puttering around with my Powermac 7100/66 and while they're a steadfast beast, it's a bit on the slow side.
Perceptions are interesting.
10C in winter is almost t-shirt weather but 10C in summer means you need to go get your coat.

I remember a printer (whom I knew quite well) invested in a 7100 back in 1995/6 and he sang its praises: it flew. He was very impressed with but he was upgrading from a IIci.
Can it be that you have Mac OS 9.0, rather than Mac OS 7.1.2 & 8.1, on there and you are expecting software from 1999 to run well on it?
Or is it more than you have become used to faster speeds and it simply seems sluggish?
I think of the NuBus macs as the end of the 68K era, rather than the beginning of the PPC, even if it has a PPC 601 chip in there.

Also the PDS flatflex cabling only allows you to use the HPV card while the Sonnet processor is in the PDS slot. All it does is save the need to get a NuBus card. And while these are becoming pricey anyway, I find that for gaming any card that can give me 1024x768 @256 colours is more than enough. The HPV is a good card but it's not that much better. It might help avoid flooding the NuBus-90 bus though.

I have both the cable and the processor from Sonnet and I'll take pictures of them for you but I'm not sure how much they will help. I would very happy if you made them available for sale to the general NuBus-mac owning market. There is surely a small but steady market for these.

The easiest ways to improve performance on the 7100 are:
1. SCSI2SD v6, BlueSCSI etc.
2. Lots of RAM (64MB+) and set up a RAM disk. Your 7100 doesn't actually need all that much RAM.
3. A 10/100-bit ethernet card may help if you have lot of network traffic.
4. There are options that have become expensive like an LVD SCSI card, Sonnet/NewerTech processors and so on and with the prices they are going for these days, it makes more sense to pick up a G4 tower for one third the price.

Others may have a better idea as to what the optimal Mac OS to run on a 7100 is. I ran System 7.1.2, Mac OS 8.1 and Mac OS 9.1 on my PM 8100. Mac OS 8.1 should probably be the fastest, given that it has more PPC-optimised code in it but System 7.1.2 always seemed quite zippy to me.
 

Byrd

Well-known member
Search the forums; a year or two ago didn't someone try to replicate the same (or at least it was for a 6100 right angled adapter)?
 
Can it be that you have Mac OS 9.0, rather than Mac OS 7.1.2 & 8.1, on there and you are expecting software from 1999 to run well on it?
Completely understood; I'm running 8.6 on it and the only time I really notice that it's a bit slow is when using things like Classilla (which may be the fault of the AAUI being hobbled at 10Mb). I haven't gotten too far into rebuilding my software library since I picked up this thing *mumble* years ago.

The problem I'm having is that if I don't use the PDS Video Card, my video options are pretty clamped down since it uses onboard memory (of which I'm stocked with 140Mb.)

It's not that I'm expecting a 7100 to be my daily driver, but it has that wonderful feeling of being able to sit down and just use a thing with all the distractions abstracted away. Kinda like how using a PB150 to write and do small HC development feels.

Plus, it's a nice bit of a challenge to effectively pull something like this back from the brink of oblivion using contemporary solutions. And if it makes a NuBus Mac that much more tenable for the neophytes and helps put a bit of vim into the old stock in the marketplace, it can only help things.

[EDIT] Another nice upgrade is to use a SCA to 50 Pin SCSI connector; you can generally get 10k/15k drives that work a treat instead of relying on an aging stock of standard drives in the resale marketplace.
 
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I've been looking for the chassis and flex cabling for a long time, they seem very hard to find...
I think the primary thing for the chassis is just to get someone to sit down for a few days with one and model it up in 3D. The primary purpose of the chassis is to just put the PDS video card in the right place to fit through the NuBus slot (upside down) and do so stably.
 

jeremywork

Well-known member
Thanks very much! This saves me from having to take out my cable. I'm not sure how often I can take it out. It has already been in 3 macs.
Sure thing! Luckily I hadn't installed this one yet.

I think the primary thing for the chassis is just to get someone to sit down for a few days with one and model it up in 3D. The primary purpose of the chassis is to just put the PDS video card in the right place to fit through the NuBus slot (upside down) and do so stably.
Here's some measurements of mine, which arrived with an AV card.
SonnetPDSframe.jpg

The Sonnet manual indicates there are different spacer configurations for 7100 vs 8100 and AV vs HPV cards.
On a different occasion I fabricated some missing spacers by cutting and drilling a junk PCI bracket (bad photo attached.)
Screen Shot 2022-05-15 at 3.34.54 PM.png

Could you do a big favor and peel back the 7181A sticker and get a pic of the chip?
@Bolle is correct (unsurprisingly)
IMG_0837.jpg

Also wondering if anyone with the Newer Tech 7100/8100 upgrade cable and frame can help out?
I have one of these in a different machine. It's not nearby at the moment, but I can eventually get to it. The ribbon cable on these is soldered directly to the edge of the CPU upgrade PCB, so it may be less useful. The mounting bracket accomplishes the same function, but it's metal and employs cable extenders for the ports. A little more stable, but more complex to replicate.

newer-tech-7mx7181-processor-300mhz-g3-for-71008100-with-apple-820-0-1.27__04847.1490187451.jpg
 
Here's some measurements of mine, which arrived with an AV card.
SonnetPDSframe.jpg
Excellent!

I have one of these in a different machine. It's not nearby at the moment, but I can eventually get to it. The ribbon cable on these is soldered directly to the edge of the CPU upgrade PCB, so it may be less useful. The mounting bracket accomplishes the same function, but it's metal and employs cable extenders for the ports. A little more stable, but more complex to replicate.

View attachment 41755
That's odd, the version I snagged off eBay must be a different revision where the cable seats on a pin header. (Don't have the board yet, still have to ask the seller about shipping status.)
s-l1600-2.jpgs-l1600-3.jpg
 
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