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Power Mac 6100 Crescendo Hack

greystash

Well-known member
Does anyone know of a hack that will allow an AV/Display card to work with the Crescendo G3 card? From what I've been able to find the only reason support was disabled was because of the limited space in the 6100 and heat issues. It works fine but the CPU extension disables itself once it loads so there is no acceleration. Is there any way to get around this?
This is the Crescendo upgrade I have: https://everymac.com/upgrade_cards/sonnettech/crescendo_g3_nubus/crescendo_g3_250_nubus.html

IMG_2202.JPG
 

macuserman

Well-known member
That's a new one for me, I've never seen that before. I was quite sure that I've seen this combo used before. I suppose it's possible you have an early rev of the G3 or something where this was an issue?
 

Trash80toHP_Mini

NIGHT STALKER
Interesting, G3 + HPV with its four VRAM SIMMs on board might very well draw more power than the PDS spec allows? I wonder it it might work without the SIMMs?

edit: OOPS! Now I wonder about power requirements of the AV Card as well, very curious. Is there a way to hack the 6100 ID to 7100? Does AV draw more power or put out more heat than HPV? Could be an RFI problem fixed in later versions? At 250MHz I'd think it would be a very(?) early version, what's the copyright date on the G3 PCB?
 
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Nixontheknight

Well-known member
Interesting, G3 + HPV with its four VRAM SIMMs on board might very well draw more power than the PDS spec allows? I wonder it it might work without the SIMMs?

edit: OOPS! Now I wonder about power requirements of the AV Card as well, very curious. Is there a way to hack the 6100 ID to 7100? Does AV draw more power or put out more heat than HPV? Could be an RFI problem fixed in later versions? At 250MHz I'd think it would be a very(?) early version, what's the copyright date on the G3 PCB?
you can use Wish I were... to make the system think it's a 7100
 

Phipli

Well-known member
Interesting, G3 + HPV with its four VRAM SIMMs on board might very well draw more power than the PDS spec allows? I wonder it it might work without the SIMMs?

edit: OOPS! Now I wonder about power requirements of the AV Card as well, very curious. Is there a way to hack the 6100 ID to 7100? Does AV draw more power or put out more heat than HPV? Could be an RFI problem fixed in later versions? At 250MHz I'd think it would be a very(?) early version, what's the copyright date on the G3 PCB?
I suspect it is an early Crescendo or driver. The AV card works fine in my 6100+Crecendo G3, although the HPV doesn't.
 
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Phipli

Well-known member
The problem isn't likely the 6100 - the AV card will work fine in a 6100 with a vanilla riser card. The issue is with the Sonnet card or software.
 

Trash80toHP_Mini

NIGHT STALKER
I suspect it is an early Crescendo or driver. The AV card works fine in my 6100+G3, although the HPV doesn't.
Just looked over the spec. Gotta be an early card at 512K Cache and wonky, self adjusting clock kluge I'd think.

Does the VRAM on HPV have a physical interference problem or is it locked out by AutoConfigure?
Sonnet's unique "AutoConfigure" technology detects what type of computer is being used and sets the speed to the maximum safe setting.
Again, Power/Cooling Budget?

edit:
Speed is a system clock multiple arrangement = not wonky. But every model/speed/release has this footnote:
5. Incompatible w/ the Power Mac 6100 AV and DOS-compatible models
What happens with HPV?
 
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Phipli

Well-known member
Does anyone know of a hack that will allow an AV/Display card to work with the Crescendo G3 card? From what I've been able to find the only reason support was disabled was because of the limited space in the 6100 and heat issues. It works fine but the CPU extension disables itself once it loads so there is no acceleration. Is there any way to get around this?
This is the Crescendo upgrade I have: https://everymac.com/upgrade_cards/sonnettech/crescendo_g3_nubus/crescendo_g3_250_nubus.html

View attachment 47246
I have two variants if the Sonnet card, each with the heatsink on the oposite side to each other. Is your heatsink towards or away from the chassis?

The heat is genuinely an issue on the ones with the heatsink near the case - I'd suggest adding a fan if possible if you are going to try getting it running with the AV card.

See attached. Both Sonnets - the black one has the heatsink on the reverse side to the PDS slot.

Really daft suggestion, but have you considered swapping your card with someone who has one of the same spec but other design in an 8100/7100?
 

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greystash

Well-known member
Thank you everyone for the suggestions! I ended up getting it working!

It is the black heatsink version, and it's actually 225Mhz, I thought it was 250Mhz.

I tried updating to the latest Sonnet driver but that didn't do anything. Next I installed Wish and set my machine ID to a PM7100, then I renamed the extension so it would load before the Sonnet extension. After rebooting the machine crashed while loading the Wish extension. Next I reverted the name of Wish and renamed the Sonnet Extension to " Zonnet..." so it loaded after Wish. This worked!

I now have a G3 PM6100 @ 225Mhz with 136MB RAM, and now I need to install my 4x 512Kb VRAM modules (thanks to Mr. Fahrenheit) to the display card.

I'll definitely add a fan and some heatsinks, it was getting pretty toasty..

Thanks everyone!

IMG_2205.JPGIMG_2207.JPG
 
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Trash80toHP_Mini

NIGHT STALKER
That's not the AV card, that's the HPV card, no mention of it being incompatible and as opposed to AV, it's worth installing! ;)

Check bus speeds of 7100/6100 against each other. If you have a 66MHz 6100 you should be OK as they match up at the 33MHz mark. If it's a 60MHz 6100 you may have a problem as the card will be expecting a 33MHz clock under Wish? Overclocking the 60MHz version ought to work as the board's CPU will be shut down anyway?

Mismatched clocks can't be good.

edit: do the 7100/66 and 7100/80 have different IDs in Wish?
 
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zefrenchtoon

Well-known member
Thank you everyone for the suggestions! I ended up getting it working!

It is the black heatsink version, and it's actually 225Mhz, I thought it was 250Mhz.

I tried updating to the latest Sonnet driver but that didn't do anything. Next I installed Wish and set my machine ID to a PM7100, then I renamed the extension so it would load before the Sonnet extension. After rebooting the machine crashed while loading the Wish extension. Next I reverted the name of Wish and renamed the Sonnet Extension to " Zonnet..." so it loaded after Wish. This worked!

I now have a G3 PM6100 @ 225Mhz with 136MB RAM, and now I need to install my 4x 512Kb VRAM modules (thanks to Mr. Fahrenheit) to the display card.

I'll definitely add a fan and some heatsinks, it was getting pretty toasty..

Thanks everyone!

View attachment 47259View attachment 47260
Good to know !!

I hope that my purple accelerator card will work with my HPV ... :eek:
As you, I need to find VRAM SIMMs too. I thought about SiliconInsider's ones but they are a bit expensive (it would cost me more than the card itself). Does any one know if they are the same SIMMs than those in LC475 ? :unsure:
 

greystash

Well-known member
That's not the AV card, that's the HPV card, no mention of it being incompatible and as opposed to AV, it's worth installing! ;)

Check bus speeds of 7100/6100 against each other. If you have a 66MHz 6100 you should be OK as they match up at the 33MHz mark. If it's a 60MHz 6100 you may have a problem as the card will be expecting a 33MHz clock under Wish? Overclocking the 60MHz version ought to work as the board's CPU will be shut down anyway?

Mismatched clocks can't be good.

edit: do the 7100/66 and 7100/80 have different IDs in Wish?
Sorry I got the name wrong, and yeah it's strange that the Sonnet extensions picks it up as an AV card.
The 7100 has a 33Mhz bus vs 30Mhz in the 6100/60 which I am using. When running metronome with the Wish gestalt ID changed it still reports the bus running at 30Mhz on the G3. Does that sound right? I did notice at one point some video artifacts on the screen but I assumed this was either due to bad capacitors on the HPV/6100 or heat. After putting a fan in and securing the HPV a little better they went away after a reboot.

I do have a 6100/66 but it's in desperate need of a recap and freezes constantly/refuses to boot.
 

greystash

Well-known member
Good to know !!

I hope that my purple accelerator card will work with my HPV ... :eek:
As you, I need to find VRAM SIMMs too. I thought about SiliconInsider's ones but they are a bit expensive (it would cost me more than the card itself). Does any one know if they are the same SIMMs than those in LC475 ? :unsure:
You should get in touch with @MrFahrenheit who I bought mine from. They are a little expensive but they're worth it. I noticed a huge difference in the 6100, EV Override was super smooth and I'll try out EV Nova tomorrow (although not expecting as much from that).
 

MrFahrenheit

Well-known member
You should get in touch with @MrFahrenheit who I bought mine from. They are a little expensive but they're worth it. I noticed a huge difference in the 6100, EV Override was super smooth and I'll try out EV Nova tomorrow (although not expecting as much from that).

Thanks for the reference, @greystash but I no longer offer any for sale, due to numerous reasons.
 

Phipli

Well-known member
That's not the AV card, that's the HPV card, no mention of it being incompatible and as opposed to AV, it's worth installing! ;)
The HPVs are generally less compatible with 6100s than the AV. HPVs don't work in my 6100.
Check bus speeds of 7100/6100 against each other. If you have a 66MHz 6100 you should be OK as they match up at the 33MHz mark. If it's a 60MHz 6100 you may have a problem as the card will be expecting a 33MHz clock under Wish? Overclocking the 60MHz version ought to work as the board's CPU will be shut down anyway?

Mismatched clocks can't be good.

edit: do the 7100/66 and 7100/80 have different IDs in Wish?
It shouldn't matter whether it is 60 or 66MHz - the sonnet setup wirks out multipliers dynamically based on the computer's bus speed.

The 7100 has a 33Mhz bus vs 30Mhz in the 6100/60 which I am using. When running metronome with the Wish gestalt ID changed it still reports the bus running at 30Mhz on the G3. Does that sound right?
The bus speed is set in hardware on the logic board, Wish I Were won't change it. It shouldn't be an issue.
 

Trash80toHP_Mini

NIGHT STALKER
Interesting stuff all around. What's the problem with the HPV card? Seems strange that everymac specifically states that AV is incompatible, but doesn't mention any problems with HPV. DOS incompatibility is based on its adapter being a 68040 converter for the Quadra board IIRC.

It shouldn't matter whether it is 60 or 66MHz - the sonnet setup wirks out multipliers dynamically based on the computer's bus speed.
Yep, that's what it sounds like. I have a 6100/60 and am now curious about the possibility of overclocking to 33MHz as the G3 will be doing the work so native 60MHz CPU won't be problematic? 10% system bus uptick would be a nice little kick in the pants! :D
 

greystash

Well-known member
The HPVs are generally less compatible with 6100s than the AV. HPVs don't work in my 6100.

It shouldn't matter whether it is 60 or 66MHz - the sonnet setup wirks out multipliers dynamically based on the computer's bus speed.


The bus speed is set in hardware on the logic board, Wish I Were won't change it. It shouldn't be an issue.
Thanks @Phipli, that's good to know!
@Trash80toHP_Mini if you do end up overclocking I'd love to know how you accomplish this! Good luck if you try it!

Update:
The 6100 is blazing fast now, OS 7.6 is incredibly quick even with a 1GB Quantum Fireball, 8.5 is very good too but I'm going to downgrade to 8.1. I ran EV Nova on Mac OS 8.5 and it ran surprisingly well! It stuttered a little in busy scenes but it was totally playable which I've never been able to achieve on a 1st generation Power Mac (running in 1024x768). I tried it with the accelerator on my 7100 but it was still too slow, with the added video improvements in my 6100 there is a huge difference in performance.

There haven't been any more video artifacts since I've left a fan in the machine so it must be heat/capacitor related.

Now to recap everything!
 
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Trash80toHP_Mini

NIGHT STALKER
@Trash80toHP_Mini if you do end up overclocking I'd love to know how you accomplish this! Good luck if you try it!
Looks like it might go to 80MHz with a 40MHz Crystal Can upgrade. That'd be with standard CPU? ISTR that being the maximum bus clock supported by the accelerator? Slower Processor on the board won't be the limiting factor. Guessing components on the board are the same as those on the faster 7100/8100 models, so glitchy subsystems like FDD and such shouldn't be a factor as on 68K overcklocking?

33% faster system bus should be one hella' kick in the pants for your rig. When you're recapping, installing a socket for the can would be a good idea? Benchmarking it at 60MHz, 66MHz and 80MHz ought to be interesting. ;)


I have a spare logic board for my long term NuBus PPC project. I'll have to see how the Radius 81/110 Big Metal Can likes a 133MHz system bus upgrade for its G3/HPV2/4.🤪
 
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