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Beige G3 RAM and PSU questions:
Posted by: Trash80toHP_Mini on 2026-04-08 12:18:41
Great, is that for a set of three as well?

Thanks for the Cache Slot info, getting more and more curious about these machines I had never even wanted to collect.
Posted by: Phipli on 2026-04-08 12:19:06
This on the other hand is actually a PC floppy drive connector. There was a prototype Perch card that had a load of PC hardware on it, AI forget what exactly, but things like a PC sound chip, PS2 and perhaps a parallel port.

1000034947.jpg
Posted by: Phipli on 2026-04-08 12:19:58
Great, is that for a set of three as well?
Last time I bought some it cost me £6 for 4 of them. But you need to keep an eye open and find deals.
Posted by: croissantking on 2026-04-08 12:21:18
There was a prototype Perch card that had a load of PC hardware on it, AI forget what exactly, but things like a PC sound chip, PS2 and perhaps a parallel port.

You kept that quiet! Is there any more info about this?
Posted by: Phipli on 2026-04-08 12:21:24
Last time I bought some it cost me £6 for 4 of them. But you need to keep an eye open and find deals.
Sorry, 6 of them, for £6. Just checked my purchase history.

1000034949.jpg
Posted by: Phipli on 2026-04-08 12:22:18
You kept that quiet! Is there any more info about this?
No idea, there aren't any around so it is kind of a moot point.
Posted by: Phipli on 2026-04-08 12:27:42
I think it was planned to be called "Web" (to go with Whisper, Wings etc) and was for CHRP machines, including ones to run Windows NT for PPC.
Posted by: Trianon on 2026-04-08 12:33:10
My beige G3 has this stick of 64 MB, 4 chips on both sides.

20260405_204220.jpg
Posted by: Trianon on 2026-04-08 12:35:42
And 2 of these, only 32MB with 8 chips on both sides
20260405_204315.png
Posted by: Durosity on 2026-04-08 12:42:10
This on the other hand is actually a PC floppy drive connector. There was a prototype Perch card that had a load of PC hardware on it, AI forget what exactly, but things like a PC sound chip, PS2 and perhaps a parallel port.

View attachment 97505
Has anyone ever tried to get a PC floppy drive to work with a retail board?
Posted by: Phipli on 2026-04-08 12:44:58
Has anyone ever tried to get a PC floppy drive to work with a retail board?
Haven't heard. I don't think so.

Can't remember if it is wired into the Mac chip (which does support PC drives) or only into the Perch slot. Can probably find out.

Edit : I believe it was planned to work in a normal Beige G3. Not sure if any motherboard straps require setting.
Posted by: Trash80toHP_Mini on 2026-04-08 12:49:30
Maybe desolder the FDD connector and hotwire it from the solder side? In doing so, the PC connector could be installed and tested without loss of Mac Floppy connection. Using both would be cool.
Posted by: Phipli on 2026-04-08 12:52:05
Maybe desolder the FDD connector and hotwire it from the solder side? In doing so, the PC connector could be installed and tested without loss of Mac Floppy connection. Using both would be cool.
I wouldn't recommend it. I'd take the overlaid footprints as a hint that they're not intended to be used at the same time.

It would have been less effort to not overlay them, therefore it was intentional.

Edit - yeah, they use common signals so it would cause issues
Posted by: Trianon on 2026-04-08 13:04:06
You will also need to add an extra power cable when using the PC style diskdrive ?
Posted by: Phipli on 2026-04-08 13:19:54
You will also need to add an extra power cable when using the PC style diskdrive ?
These boards work with ATX PSUs, but it isn't hard to put an adapter from molex.

I wouldn't bother though - the Mac style floppy is better because it reads 800k Mac disks.
Posted by: CC_333 on 2026-04-08 13:27:42
I wouldn't bother though - the Mac style floppy is better because it reads 800k Mac disks.
People will try a PC drive on the Beige G3 because they can, not because it's better! 😀

c
Posted by: croissantking on 2026-04-08 13:28:16
Has anyone ever tried to get a PC floppy drive to work with a retail board?
Haven't heard. I don't think so.

Can't remember if it is wired into the Mac chip (which does support PC drives) or only into the Perch slot. Can probably find out.

Edit : I believe it was planned to work in a normal Beige G3. Not sure if any motherboard straps require setting.

I briefly looked into this and its wired directly into the Heathrow/Mac-io chip. There is MFM support in ROM so it would probably work without any further hacks.
Posted by: Trash80toHP_Mini on 2026-04-08 13:34:43
These boards work with ATX PSUs, but it isn't hard to put an adapter from molex.
Interesting, will they go straight from a 24Pin source to a 20Pin adapter cable w/o modification to the adapter?

I wouldn't bother though - the Mac style floppy is better because it reads 800k Mac disks.
Makes sense, only have room for a single Laptop FDD in the 2UBG3 anyway.
Posted by: Phipli on 2026-04-08 13:40:23
Interesting, will they go straight from a 24Pin source to a 20Pin adapter cable w/o modification to the adapter?
The pinout is compatible with 20 pin ATX. The tower PSU is basically an ATX PSU. The desktop one has the soft power the Mac way instead of the ATX way, so if you want to use a board out of a desktop with ATX you have to swap Jumper J28 over to the other position (it's in the corner near the back of the end PCI slot.

If you move a tower board into a desktop or vice versa, and are wondering why it powers on as soon as you plug it in? Swap J28 over. It just inverts the soft power logic.

1000034954.jpg
Posted by: Durosity on 2026-04-08 13:40:47
There is MFM support in ROM so it would probably work without any further hacks.
Sounds like a fun little project 😉
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