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R7000 beige G3 issues

I think I’ll stick to the ATI card and try different driver versions.
Roger that.
I'm circling back to this issue, as I have a new G4 ZIF that I DIYed from a 466MHz DA card. It's quite a beauty - it runs stable at 567MHz.
At the risk of going off-topic, I'd just like to acknowledge how awesome this is. First of all, are you running at 66.6MHz * 8.5 = 567MHz? I didn't think the 7400 supported an 8.5x multiplier. Are you using a factory (Raytheon, Fairchild?) VRM? How are you cooling it?
 
This page claims that a B&W G3 or newer is required. I'm not sure why.
If the card can work in a B&W G3 then it might work in an older Mac.
Nvidia cards 4MX, 4600, 6200, 6600, 7800, FX4500 have fcode that is conditionally compiled.
Those require modification to work in Old World Macs.
Conditionally compiled fcode is from Forth code that defines words inside an if ... then
Search for colon definition words that are defined in code that is indented. Use grep -e '\t:' on the output produced by DumpPCIRom.sh. The Forth code produced by DumpPCIRom.sh can be modified (add patches and debugging and logging and such) and converted back to fcode using toke from
https://github.com/joevt/OpenBIOSStuff

A PCIe FX 4500 or 7800 GT with modified fcode can work in an Old World Mac that only has PCI:
https://forums.macrumors.com/thread...l-work-in-a-beige-power-macintosh-g3.2303689/
https://forums.macrumors.com/thread...eige-power-macintosh-g3.2303689/post-33238601
 
Roger that.

At the risk of going off-topic, I'd just like to acknowledge how awesome this is. First of all, are you running at 66.6MHz * 8.5 = 567MHz? I didn't think the 7400 supported an 8.5x multiplier. Are you using a factory (Raytheon, Fairchild?) VRM? How are you cooling it?

:) :)

I'm actually more amazed that this 7400 can manage 567MHz with a 2:1 backside cache setting. It'll even POST at 610MHz.

I'm running a 6.5x multiplier on a non-standard 87.4MHz bus. I swapped in a 100MHz XPC106 chip on the logic board, and I swapped the stock 14.31818MHz reference crystal with a 15MHz crystal (I've experimented with faster).

I've got a Switch Power VRM installed, which has been recapped (I've heard that Raytheons are better, any truth to that?).

For cooling, I've currently only got the stock heatsink fitted, but as long as the case is closed such that the PSU fan pulls air across it, it idles around 40C/104F. I've got one of these on order, which I'll mount where the hard drive usually sits:

Screenshot 2025-08-12 at 23.52.29.png
 
There's some wild stuff going on in those MacRumors threads, @joevt.

Because this is my kind of fun, I bought a cheap PCI Geforce4 MX just to play with.
 
@croissantking, that's a seriously hotrodded Beige. Thanks for the info. Are your PCI cards running at 35MHz then?

I've never heard of a Switch Power VRM. I just know Royal is the one to avoid.

I'm planning on building my own DIY G4 ZIF eventually and it's nice to know that a 7400 clocked that high will work without blowing up the VRM. I have a Raytheon, we'll see how it goes.
 
@croissantking, that's a seriously hotrodded Beige. Thanks for the info. Are your PCI cards running at 35MHz then?

I've never heard of a Switch Power VRM. I just know Royal is the one to avoid.

I'm planning on building my own DIY G4 ZIF eventually and it's nice to know that a 7400 clocked that high will work without blowing up the VRM. I have a Raytheon, we'll see how it goes.

Yes, PCI is at 35MHz.

My VRM looks like the one on this page: https://www.kiechle.com/vrm/. I'd actually quite fancy one of those Royal VRMs just as a showpiece!
 
Because this is my kind of fun, I bought a cheap PCI Geforce4 MX just to play with.
I for one would be pretty excited to see cards like the 2MX and 4MX working in OldWorld machines. Right now I have a 6500 that can't use ATI cards for 3D acceleration due to some sort of conflict with the onboard ATI hardware. Granted, an OS new enough for a nvidia card is new enough to bog down a 6500... so there is that, but it's still neat.
 
I for one would be pretty excited to see cards like the 2MX and 4MX working in OldWorld machines. Right now I have a 6500 that can't use ATI cards for 3D acceleration due to some sort of conflict with the onboard ATI hardware. Granted, an OS new enough for a nvidia card is new enough to bog down a 6500... so there is that, but it's still neat.
There’s always 3DFX, if you’re running OS 9…
 
And there’s the very real possibility to replace the Ati Rage II on the 6500 with a Rage Pro, and double the SGRAM to 4 mb… im actually exploring this possibility!
 
And there’s the very real possibility to replace the Ati Rage II on the 6500 with a Rage Pro, and double the SGRAM to 4 mb… im actually exploring this possibility!

Yes, there’s no reason you couldn’t do the GPU chip swap. The SGRAM I’m guessing would be more fiddly - would you ‘piggy-back’ the new chips on top of the existing ones?

Of course, this wouldn’t help with the ATI conflict.
 
I can't speak for the Yikes G4, but I have a XLR8 G4 upgrade in my G3 Rev C tower, running at 500Mhz and it never gave me any issues with its Radeon 7000 installed. The processor also came with extensions, so maybe that has something to do with it.
 
I can't speak for the Yikes G4, but I have a XLR8 G4 upgrade in my G3 Rev C tower, running at 500Mhz and it never gave me any issues with its Radeon 7000 installed. The processor also came with extensions, so maybe that has something to do with it.
Interesting - is that a 7400 or 7410? Are you running Mac OS 9.x?
 
It's a 7400 I believe, running MacOS 8.6, 9.2.2, and 10.2.

OK, that's interesting to know. Would you be able to share a screenshot of the ATI extensions you have installed under 9.2.2, listing the versions?

And there’s the very real possibility to replace the Ati Rage II on the 6500 with a Rage Pro, and double the SGRAM to 4 mb… im actually exploring this possibility!

I have a spare Rage Pro chip and 2MB SGRAM, they're on a dead Beige G3 board. Send me a DM if you would like them.
 
I for one would be pretty excited to see cards like the 2MX and 4MX working in OldWorld machines. Right now I have a 6500 that can't use ATI cards for 3D acceleration due to some sort of conflict with the onboard ATI hardware. Granted, an OS new enough for a nvidia card is new enough to bog down a 6500... so there is that, but it's still neat.
Can't you just remove the onboard ATI hardware from Open Firmware? Remove PCI device number 12 from the list of device numbers to be probed.
https://68kmla.org/bb/index.php?threads/the-great-gazelle-pci-hack-thread-part-2.38360/post-467825
 
Hi Croissantking,
I have to be more specific! First off, thank you for the offer, I will certainly DM you for the Pro. Then, I'd like to elaborate on what I'm doing. I read a few months back a post by the great Trag, here:
link
And i started thinking. I PM'd Trag and we discussed a bit on the serious possibility to double the video RAm of the PM 6500, a possibility that would open interesting scenarios.
This can be accomplished by replacing the 1mb chips on the logic board with 2mb parts - - for a total of 4MB.
So, Jeff graciously sent me a few KM4132G512Q-10 chips, they're 256 X 32 X 2 (2MB) each, while the chips already soldered on the 6500 are MT41LC256K32D4, 128 X 32 X 2 (1MB). While the pin for BA is connected (they are both dual bank chips) the caveat here is that pins A8 and A9 are for some unfathomable reason on different pins on the memory chips footprint which is essentially the same otherwise. I will undoubtedly have to bodge some wires to solve this.
But, studying the data sheets of both memory chips, I realized I needed to know about the Rage II video chip to know where to place those bodges.
It turns out no data sheet is available for the Rage II... but there's one for the Rage Pro! And I found out that, in the PCI compatible, PQFP 208 package implementation, it is a direct, pin to pin compatible part, meant to simplify upgrading existing designs of integrated M/B graphics built around the Rage II. So, it is possible that it is a drop in upgrade for the 6500 board, adding substantial performance (at least double the acceleration, plus some other things).
This more or less sums up the research I did, however impossible to do otherwise without Trag's input and help.
 
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@pizzigri I'd like to get onboard with this, should probably break it out into it's own thread though. I'm not smart enough to faff around in OF alone, but I am dumb enough to solder random chips to my 6500. I have a PCI Rage Pro card on the way for parts and would like to follow along with the project. That's not to say I refuse to play with disabling the onboard chip in OF, but I'm a sucker for a cool project and it's in-line with my 6500's onboard RAM upgrade. And I could theoretically still disable the onboard chip if it's not fast enough anyway. :P
 
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