PM5400/5500 video upgrades? - internal display

[Trekintosh]

Howdy,

I’m picking up a PM5400 (and I impulse bought a 6500 LB) in a couple months and I was wondering if there were any video cards that could be modified to work with the internal display. I don’t mind solder work in the slightest, but I have no clue whatsoever what the word is in terms of card compatibility with PCI based Power Macs is.

 

[obsolete]

It's been done on the G3 AIO, and it could probably be done in the 5x00 as well, but the plastic on them is so brittle at this point, I don't think it's possible to take one apart to mod and put it back together without destroying too many pieces

 

[Daniël]

It's been done on the G3 AIO, and it could probably be done in the 5x00 as well, but the plastic on them is so brittle at this point, I don't think it's possible to take one apart to mod and put it back together without destroying too many pieces

On the G3 AIO, there is a separate cable to carry VGA video from the graphics card to the monitor, which means you can modify a different PCI card by soldering a female IDC pin connector through ribbon cables to the right solder joints of the VGA connector, in order to connect it.
For the 5500, it's a bit more difficult but not impossible.

Looking at the schematic of the 6500/5500/TAM board, the signals you need to tap into that go from the ATi chip to the edge connector are red, green and blue video, HSync, VSync, Monitor ID 1 and 2, and ground.
You can see in the schematic that at least for the MonID and sync signals, there are resistors you could remove to sever the connection, which you would solder wires to going to an IDC connector on the side of the resistor that connects to the board's edge connector, with wires going to the same VGA signals on the installed PCI card (for the right ID signals, it's MonID 1 to VGA Pin 12, MonID 2 to VGA Pin 15).

The problem is that I don't see any resistors or such on the R, G and B lines going from the ATi chip to the edge connector, so the only option would be to sever traces and solder to the edge connector's solder joints for those lines, which is relatively destructive.
Another issue is that you'd still have the ATi chip active as the main monitor, which you now can't actually use.

You'd have to find a way to disable the ATi chip entirely (with the most extreme option being the removal of the chip, this is possible), which then also adds the issue that the TV and Video In will no longer work.
The Video In and TV signals go through an interface chip on the board to turn it into 8-bit digital video, which is the same as on a PC's graphics card's VESA Feature Connector, which obviously won't work if the ATi chip it's going to is disabled/missing.

It could be possible to also tap those signals off the board and feed them to the feature connector on the upgraded graphics card, if it has one, but it's getting very complex at that point.
I actually plan on trying this on a 6500 board that I have, which will go into a PC case, as I removed the ATi chip specifically to steal its PCI resources to add back the ability to install three PCI cards into the system, specifically so I could install a better graphics card without losing one of two PCI slots.

 

[chelseayr]

I know its not quite the same thing but I guess that one could use a voodoo2 card to basically do ati>3dfx>tube 'loop' internally? as even a more basic card like that still has some particular improvements over the onboard chip

I can't find the specific rage/voodoo one I know was out there but even then these two quick-to-find-from-web unrelated comparisons nevertheless shows my relative point regarding 3dfx;

https://vintage3d.org/images/voodoo/glquake.jpg

https://i.ytimg.com/vi/75UtKz9RYEg/maxresdefault.jpg

 

[Trash80toHP_Mini]

Limitation is the craptastic display in the AIO 5x00 series. It's doubtful you could go to an acceptable 1024x768 on that CRT/flyback?

 

[Trekintosh]

Limitation is the craptastic display in the AIO 5x00 series. It's doubtful you could go to an acceptable 1024x768 on that CRT/flyback?

I mean, the 5500 supports up to 1280x1024 on the internal display.

Really my desire for more video performance is less for resolution and more for games. Yeah I’ve got a G3 iMac that would blow the pants off the AIO, but where’s the fun in doing what’s sensible?

 

[Trekintosh]

On the G3 AIO, there is a separate cable to carry VGA video from the graphics card to the monitor, which means you can modify a different PCI card by soldering a female IDC pin connector through ribbon cables to the right solder joints of the VGA connector, in order to connect it.
For the 5500, it's a bit more difficult but not impossible.

Looking at the schematic of the 6500/5500/TAM board, the signals you need to tap into that go from the ATi chip to the edge connector are red, green and blue video, HSync, VSync, Monitor ID 1 and 2, and ground.
You can see in the schematic that at least for the MonID and sync signals, there are resistors you could remove to sever the connection, which you would solder wires to going to an IDC connector on the side of the resistor that connects to the board's edge connector, with wires going to the same VGA signals on the installed PCI card (for the right ID signals, it's MonID 1 to VGA Pin 12, MonID 2 to VGA Pin 15).

The problem is that I don't see any resistors or such on the R, G and B lines going from the ATi chip to the edge connector, so the only option would be to sever traces and solder to the edge connector's solder joints for those lines, which is relatively destructive.
Another issue is that you'd still have the ATi chip active as the main monitor, which you now can't actually use.

You'd have to find a way to disable the ATi chip entirely (with the most extreme option being the removal of the chip, this is possible), which then also adds the issue that the TV and Video In will no longer work.
The Video In and TV signals go through an interface chip on the board to turn it into 8-bit digital video, which is the same as on a PC's graphics card's VESA Feature Connector, which obviously won't work if the ATi chip it's going to is disabled/missing.

It could be possible to also tap those signals off the board and feed them to the feature connector on the upgraded graphics card, if it has one, but it's getting very complex at that point.
I actually plan on trying this on a 6500 board that I have, which will go into a PC case, as I removed the ATi chip specifically to steal its PCI resources to add back the ability to install three PCI cards into the system, specifically so I could install a better graphics card without losing one of two PCI slots.

Thanks! Lots of excellent info in here! Good point on the phantom display. I haven’t messed with multi monitor setups in classic Mac OS in a long long long time, is there no way to disable a connected display in software?

Do keep us posted on your 6500 project! Got a thread for it?

 

[Trash80toHP_Mini]

I mean, the 5500 supports up to 1280x1024 on the internal display.

Be that as it may, the 5400 is limited to 1024x768. ATI graphics subsystem on the PCI bus of the 5500/6500 was a massive upgrade. My take on this would be that the CRT/Flyback etc. was likely upgraded to support that capability as well?

 

[Trekintosh]

Be that as it may, the 5400 is limited to 1024x768. ATI graphics subsystem on the PCI bus of the 5500/6500 was a massive upgrade. My take on this would be that the CRT/Flyback etc. was likely upgraded to support that capability as well?

I doubt it. According to all the research I’ve done, X500 logic boards go straight into the 5400 and earlier chassis without issue. I feel like if trying to use max resolution exploded the CRT, someone would have mentioned that. 1280x1024 is not a high end resolution even at the time, and retooling the monitor in an all in one between generations that are so close together seems needlessly expensive.

 

[Byrd]

1280 X 1024 is a lot to ask of a 15” CRT, I’ve found 832 X 624 the sweet spot for 5x00 CRTs, with 1024 X 768 OK for short use.

I’d love to see a switch between internal and external video output, Voodoo at the ready.

 

[Trekintosh]

Oh that’s a good point I didn’t even consider. Is there any reason I couldn’t use an external monitor with a PCI GPU?

 

[Byrd]

No, nothing stopping you however if an ATI PCI video card (7000/9000) there can be a tricky juggle with Mac OS supplied and OEM ATI video drivers to get both internal and external acceleration. Hence Voodoo which just needs a couple of drivers to run and no fuss.

 

[Trekintosh]

Hmm, all compelling points. I’ll look into it. From the lack of mention i’m assuming nvidia cards weren’t much of a thing on PCI Macs.

 

[Byrd]

For PCI and < Mac OS 9, correct there isn’t much out there for nVidia PCI cards with driver support. Maybe a flashed GeForce 2 PCI, but don’t think I’ve ever seen one.

 

[Trekintosh]

I threw out an insulting lowball offer on a "For Parts" Voodoo 2 and they accepted it! I think the "for parts" was just user error, we'll see once it and the Mac shows up. I do like the idea of the loopthrough system and it's confirmed that the Voodoo 2 will play Elite Force which is really all I care about. Yeah I know the 603e is gonna be too slow for good gameplay since the game demands a G3, but at least that's much more easily solvable than video upgrades.

 

[Byrd]

Enjoy! Might be worth testing the card in a PC first to check it works if not dos utility mojo tells more. Chuck a fan somewhere nearby in the 5500 they do get hot.

 

[MacJunky]

For PCI and < Mac OS 9, correct there isn’t much out there for nVidia PCI cards with driver support. Maybe a flashed GeForce 2 PCI, but don’t think I’ve ever seen one.

I'd really like to know if those work in OldWorld machines. I recently put sockets on a GF2MX and 4MX and tried a bunch of different ROMs in my 6500 with no luck... But perhaps they are the wrong cards or were already dead, IDK, I don't have a PC with PCI to test them in.

Yeah I know the 603e is gonna be too slow for good gameplay since the game demands a G3, but at least that's much more easily solvable than video upgrades.

I don't want to ruin your fun or stop you from trying, but I will say that Elite Force was rough on a 333MHz Tray Loading iMac G3 with max VRAM, so take that however you want. Though I do understand that you are basically the flipped version of that with more GPU than CPU, so you might see interesting results. It might not be that bad, and as you said, CPU upgrade card might be the answer.
I will say that with onboard graphics, StarCraft's performance still sucks and is barely playable mid to late game on my 6500/225 even if it's clocked at 300MHz. And the benchmark numbers for the CPU are absolutely dismal compared to a G3.

 

[DarthNvader]

On the G3 AIO, there is a separate cable to carry VGA video from the graphics card to the monitor, which means you can modify a different PCI card by soldering a female IDC pin connector through ribbon cables to the right solder joints of the VGA connector, in order to connect it.
For the 5500, it's a bit more difficult but not impossible.

Looking at the schematic of the 6500/5500/TAM board, the signals you need to tap into that go from the ATi chip to the edge connector are red, green and blue video, HSync, VSync, Monitor ID 1 and 2, and ground.
You can see in the schematic that at least for the MonID and sync signals, there are resistors you could remove to sever the connection, which you would solder wires to going to an IDC connector on the side of the resistor that connects to the board's edge connector, with wires going to the same VGA signals on the installed PCI card (for the right ID signals, it's MonID 1 to VGA Pin 12, MonID 2 to VGA Pin 15).

The problem is that I don't see any resistors or such on the R, G and B lines going from the ATi chip to the edge connector, so the only option would be to sever traces and solder to the edge connector's solder joints for those lines, which is relatively destructive.
Another issue is that you'd still have the ATi chip active as the main monitor, which you now can't actually use.

You'd have to find a way to disable the ATi chip entirely (with the most extreme option being the removal of the chip, this is possible), which then also adds the issue that the TV and Video In will no longer work.
The Video In and TV signals go through an interface chip on the board to turn it into 8-bit digital video, which is the same as on a PC's graphics card's VESA Feature Connector, which obviously won't work if the ATi chip it's going to is disabled/missing.

It could be possible to also tap those signals off the board and feed them to the feature connector on the upgraded graphics card, if it has one, but it's getting very complex at that point.
I actually plan on trying this on a 6500 board that I have, which will go into a PC case, as I removed the ATi chip specifically to steal its PCI resources to add back the ability to install three PCI cards into the system, specifically so I could install a better graphics card without losing one of two PCI slots.

The 5500/6500 doesn't have a 'pci-probe-list'?

Or you just wanted to free up a slot?

 

[joevt]

The 5500/6500 doesn't have a 'pci-probe-list'?

I think the only thing pci-probe-list does for 5400/6400/5500/6500 is enable/disable the pci106b,1 device.
You would have to use something like the The Great Gazelle PCI Hack to modify the list of PCI slots to probe. The 5400/6400 need a modified gazelle hack since they are not gazelle (they have a different Open Firmware version).