Power Mac 6500/250

Colleton

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Apr 20, 2022
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Hi everyone, glad to be here!

I broke down last week and bought a (doubtless) over-priced Power Mac 6500/250 on eBay. It looked to be dirty (expected), but in decent condition. The description said "no HD," and when I received it today that was indeed true. It chimes and boots, but sits at the ? drive prompt because the HD is missing.

This is my 1st late 90's PPC Mac. I have no experience with them. Low End Mac says the HD is IDE, but the machine does have an external SCSI drive connector on the rear of the computer. I have a Compact Flash to IDE adapter on order and it should be here on Sunday. I have several different mfg CF cards that I hope will work with this on hand. I also have a 250GB IDE HD from an early 2000's PC that I could use if it will work with a machine that originally shipped with a 4GB HD. I think that would be problematic though? When this machine was built in 1997 I had an 8GB HD in my PC. haha, so long ago...

At any rate, I'm trying to figure out what OS to use, and what is the best way to get it installed on the HD. I've been using a Floppy EMU (FE) for older 68K Macs, but this machine makes it impossible to use the FE unless I remove the FE case. I don't want to do that. I'm thinking of installing OS 8 on my SCSI2DS v5.5 external drive (using an LC 475 for the install) and seeing if I can boot the 6500 with that. Doable? Are there CD images for OS installers that I could download, burn to disk and boot the 6500 from that?

I'm kind of a noob with this and am looking for advice on how to proceed. Any thoughts or help would be appreciated. Thanks!
 
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Volvo242GT

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The 250GB drive will work, you may need to partition it in Drive Setup to get the Mac to recognize it. Minimum OS requirement is System 7.5.5. With the 250GB drive, you'd need to set up a 2GB or smaller partition to run System 7.5.5 or 7.6.x on it.

You can run Mac OS 9.1 without needing the OS 9 Helper patch utility that allows Mac OS 9.2-9.2.2 to install on pre-G3 PowerMacs. The Macintosh Garden - http://macintoshgarden.org - has CD images that you can burn with a modern Mac using Disk Utility and install Mac OS 8.1, 8.5, 8.6, or 9.x on the machine.
 
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eric

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use the FE unless I remove the FE case
Why's that? Unless it's changed you should be able to just pop the DB19 connector off the end and plug it into the internal IDC connection internally. (but there's no floppy install of 8! There is a MacOS 8 Disk tools image though i believe)

I'd download a 8.6 CD and boot off that (Holding down C to boot off cd) - format and install on the HDD. If you do install on a scsi2sd first - once you get the CF or IDE up, you can just select all and copy it over to there and reboot off that.
 

Colleton

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Apr 20, 2022
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My thanks to both of you for the help.

I was able to download an ISO of OS 9.04 and burn it to CD. I can boot the CD on the Power Mac, but when I run Drive Setup it doesn't see the 250GB IDE drive, just the SCSI OS 9 drive. I don't know what to do at this point, maybe the drive is bad? It's been sitting on a shelf for ~15 years.

The CF to IDE adapter will be here tomorrow, I'll try that.
 
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Volvo242GT

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Hmmm, jumpers are set correctly? I do know that Apple's early implementation of IDE wasn't that great. Basically had a requirement of 8GB being the boot partition. Do you have access to a revision 2 B&W G3 or a G4 PowerMac that can boot Mac OS 9? If so, format the drive using that and provide an 8GB first partition, then do a couple partitions for the rest of the drive, splitting the remainder in half, so Mac OS 9 will see eveything.
 
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Colleton

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Apr 20, 2022
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Hmmm, jumpers are set correctly? I do know that Apple's early implementation of IDE wasn't that great. Basically had a requirement of 8GB being the boot partition. Do you have access to a revision 2 B&W G3 or a G4 PowerMac that can boot Mac OS 9? If so, format the drive using that and provide an 8GB first partition, then do a couple partitions for the rest of the drive, splitting the remainder in half, so Mac OS 9 will see eveything.

The only jumper on the HDD is the CS/Slave/Master jumper. I've tried it in CS and Master with no good result. I have a G4 iMac I might be able to test the drive on. We'll see.

It's interesting to me that the computer has an IDE HDD, but still has an SCSI bus that is used by the CD ROM drive and the Zip drive (if present). Does anyone know why this was done?

My 6500 does not have the Zip drive, so for now I've installed a BlueSCSI on the Zip drive SCSI cable. It's working like a champ. I have the case panels removed and will begin cleaning them tomorrow. I'm going to have to retrobright the plastic on the rear of the case, it's very dark.
 

This Does Not Compute

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It's interesting to me that the computer has an IDE HDD, but still has an SCSI bus that is used by the CD ROM drive and the Zip drive (if present). Does anyone know why this was done?
Apple needed to include at least an external SCSI port so users could attach peripherals, as FireWire wasn't around at the time. Since that meant including a SCSI controller, it would cost practically nothing to include an internal SCSI bus as well. Switching the CD-ROM and Zip interfaces to IDE would have probably necessitated a second IDE controller, so the incremental cost of using SCSI CD-ROM and Zip drives over IDE ones was probably cheaper in the long run.
 
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Volvo242GT

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The only jumper on the HDD is the CS/Slave/Master jumper. I've tried it in CS and Master with no good result. I have a G4 iMac I might be able to test the drive on. We'll see.

It's interesting to me that the computer has an IDE HDD, but still has an SCSI bus that is used by the CD ROM drive and the Zip drive (if present). Does anyone know why this was done?

My 6500 does not have the Zip drive, so for now I've installed a BlueSCSI on the Zip drive SCSI cable. It's working like a champ. I have the case panels removed and will begin cleaning them tomorrow. I'm going to have to retrobright the plastic on the rear of the case, it's very dark.
Grab one of those USB to IDE external hard drive cases, then hook it up to the iMac that way. Then, try using Drive Setup on the G4 under Mac OS 9. If it works, then you can swap it in and save the BlueSCSI for another machine. Otherwise, use an IDE internal Zip drive on the IDE/ATA bus, then keep the BlueSCSI in place.
 
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Colleton

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Apr 20, 2022
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@Volvo242GT: The CF to IDE adapter I'd ordered arrived today and it ID'd and formatted with an old 4GB CF card right away. I have OS 8.6 installed on the CF drive and the computer working perfectly. Well, except for the battery. I have to source a replacement for that.

I got Doom and Doom II installed and they both run very well on this machine. I guess that Quake is next.

I have to say, this is about the most 90's looking computer ever made. lol

Thanks everyone, I appreciate the great help and advice!
 
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Volvo242GT

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Feb 7, 2022
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@Volvo242GT: The CF to IDE adapter I'd ordered arrived today and it ID'd and formatted with an old 4GB CF card right away. I have OS 8.6 installed on the CF drive and the computer working perfectly. Well, except for the battery. I have to source a replacement for that.

I got Doom and Doom II installed and they both run very well on this machine. I guess that Quake is next.

I have to say, this is about the most 90's looking computer ever made. lol

Thanks everyone, I appreciate the great help and advice!
Cool. Glad it's working.

Battery-wise, I'd be tempted to wire up a triple AAA holder and mount it somewhere away from the board. That way, you can use more common batteries to get the 4.5 volts necessary and not have to worry about the stock 4.5 volt alkaline battery deciding to let its acid out onto the board when it gives out.
 
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Colleton

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Apr 20, 2022
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Cool. Glad it's working.

Battery-wise, I'd be tempted to wire up a triple AAA holder and mount it somewhere away from the board. That way, you can use more common batteries to get the 4.5 volts necessary and not have to worry about the stock 4.5 volt alkaline battery deciding to let its acid out onto the board when it gives out.

Great idea, thanks. I have one on order now.
 
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Trash80toG4

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Apr 1, 2022
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Grab one of those USB to IDE external hard drive cases, then hook it up to the iMac that way. Then, try using Drive Setup on the G4 under Mac OS 9. If it works, then you can swap it in and save the BlueSCSI for another machine.
Definitely save SCSI mass storage solutions for IDE deprived Macs. I run my 6400/6500 TinkerTestbed off CF/Adapter and it works great. SCSI internals was not only easier, it was necessary as IDE support was rudimentary when introduced in the Quadra 630 and PB190. It hadn't improved much by the 6500 timeframe. A second bridge wouldn't work at the time as Apple hadn't figured out how to run the existing bridge at full spec. I wonder if it was ever fully implemented until the move from NuBus architecture to PCI in the PB3400. There was no real need for full spec IDE in 'Books or consumer level Macs as no provision was ever made, nor was it needed in machines designed without a spot to install a second device.

Otherwise, use an IDE internal Zip drive on the IDE/ATA bus, then keep the BlueSCSI in place.
Will a Zip drive even run on the 6500's Neolithic IDE bus? Everything I've read about early IDE said support was limited to a single HDD and nothing else. Has anyone ever reported success in running Zip off that interface? Curious to see if it would squeek by as it's almost a mass storage device.

Doubtful the drivers would support it, but with the scarcity of internal SCSI Zip drives that would make sense to tinker with now that we have SCSI solutions for SD/SSD widely available. 🤔
 

martinsmartin

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Mar 8, 2022
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Any chance you have a link to where you got one of these? Anything special to wire it up? I have couple boards that need one...

Here's an example

Wiring is completely up to you. You can snip the current battery wires and solder directly to that or make your own jumper.

You are looking to recreate something Like this

Make sure that its secured or positioned in way so it can't short anything etc.
 
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