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jmacz journey
Posted by: superjer2000 on 2025-08-29 19:53:50 Yeah, I sold it. But it went to @tt. If he still has it, you could try asking him? FWIW, 4MB worked fine and 8MB/16MB was stable but I could not get Connectix Virtual to recognize it and allow me to use the extra memory as a ram disk, etc. Thanks. The current issue im having is it never reports more than 4mb even though there is 16mb installed on the accelerator. So potentially a different issue. It seems like your accelerator actually showed 16mb as being physically installed just not usable (ie in the control panel info screen)?
Posted by: jmacz on 2025-08-29 20:16:56 Thanks. The current issue im having is it never reports more than 4mb even though there is 16mb installed on the accelerator. So potentially a different issue. It seems like your accelerator actually showed 16mb as being physically installed just not usable (ie in the control panel info screen)? Yeah, last I left it, I was only able to use 4MB but Compact Virtual was showing 8MB or 16MB depending on how much I had installed. I just couldn't get it to let me use the additional memory. But it definitely saw it.
Posted by: jmacz on 2025-08-31 22:23:15 Cooked up a system extension for System 7.6.1 that mimics Apple's hidden option in MacOS 8.6 to disable the startup ram test on Power Macintoshes. I have only tried it on my Power Macintosh 8500 on System 7.6.1. Thread on the analysis with @joevt here: https://68kmla.org/bb/index.php?threads/skipping-the-startup-memory-test.50699/ There's a post in that thread with the system extension (binhex'd stuffit archive).
Posted by: volvo242gt on 2025-08-31 23:46:34 Wonder if it'll work on my 7100/80... Am running 8.1, so it might. I'll let you know what I discover soon.
Posted by: joevt on 2025-09-01 00:33:20 Wonder if it'll work on my 7100/80... Am running 8.1, so it might. I'll let you know what I discover soon. 7100 and other PDM machines don't have the same NVRAM as CHRP machines. The test of the `CHRPNess` bit fails, so it won't do the NVRAM write for GrandCentral, OHare, or Heathrow which don't exist in the PDM machine. https://68kmla.org/bb/index.php?threads/skipping-the-startup-memory-test.50699/post-571473
Posted by: volvo242gt on 2025-09-01 09:21:17 7100 and other PDM machines don't have the same NVRAM as CHRP machines. The test of the `CHRPNess` bit fails, so it won't do the NVRAM write for GrandCentral, OHare, or Heathrow which don't exist in the PDM machine. https://68kmla.org/bb/index.php?threads/skipping-the-startup-memory-test.50699/post-571473 Thought about that a few minutes after typing my message. Did download the extension for when/if I get another G2 (PCI) machine.
Posted by: jmacz on 2025-09-01 10:44:18 Wonder if it'll work on my 7100/80... Am running 8.1, so it might. I'll let you know what I discover soon. Does Apple's hidden option in Mac OS 8.6 work on your 7100? If it does, there could be another code path.
Posted by: volvo242gt on 2025-09-01 11:07:23 Does Apple's hidden option in Mac OS 8.6 work on your 7100? If it does, there could be another code path. It may. Don't remember enough about my old 7100/80 when it had 8.6 installed. I do plan to upgrade to 8.6 on the current machine, though. Just have to find where I put the installation discs.
Posted by: jmacz on 2025-09-02 20:33:40 Not sure what's up with these PowerBook internal Zip drives, but this is the second one I have had (and I've only had two) that has exhibited issues when used. This one's in my 3400c and the last one was in my 5300c. Both cause random lock ups when inserted, with/without the driver installed, and without zip disks inserted. It just randomly locks up under 7.6.1. My old 5300 used to have the same issue. Replace it with the floppy drive, and it works fine. I don't get it. The internal hard drive is an industrial grade compact flash with an CF to IDE adapter set to master. Works great. And system is stable as long as the Zip drive isn't inserted.
Posted by: jmacz on 2025-09-06 09:09:12 Sharing some pictures of the plastic repairs on my Quadra 840AV. Used plastic weld to fill in the broken areas, then cut away the excess, sanded it down, and then painted.
Posted by: jmacz on 2025-09-07 17:00:25 That Corsair HX1200 PSU is working well. Strong solid 5V/12V/-12V at the logic board. Power on circuit is working and the relay to the passthrough power connector also is working great. Q950 boots, chimes, sound works, all looks well. Only issue however is that on a cold boot, before the chime, I get pop from the speaker (and headphone jack) before the chime plays. Only happens on cold boot, restarts are fine. After that the audio plays fine including the chime. I don't think this pop is normal. Trying to figure out what it is...
Posted by: ObeyDaleks on 2025-09-07 20:15:54 Sharing some pictures of the plastic repairs on my Quadra 840AV. Used plastic weld to fill in the broken areas, then cut away the excess, sanded it down, and then painted. Would you mind sharing what paint you used?
Posted by: jmacz on 2025-09-07 20:51:54 Would you mind sharing what paint you used? Same as usual. Rustoleum Satin Stone Gray. It's a little dark and a little cool in tone compared to the original platinum, but that usually shows mostly when it's dark. In daylight, it looks close.
Posted by: is2scooby on 2025-09-08 15:43:57 Very nice plastic repair work! I’ve never been enough of an artist (or had the patience) to achieve results like you have.
Posted by: jmacz on 2025-09-08 20:00:18 Very nice plastic repair work! I’ve never been enough of an artist (or had the patience) to achieve results like you have. Thanks!
Posted by: jmacz on 2025-09-08 20:09:07 Finished the Quadra 950 ATX converted power supply. As I mentioned before, it's using a Corsair HX1200 which is a PSU from 2016-2020 that is no longer sold but you can find them used and in good condition. It has independent regulation of the voltage rails, and provides 30A on 5V. It's an oversized PSU but works fine in the large PSU enclosure the Quadra 950 uses. For now, I'm using the standard harness board that the PSU has (ie. I am not hard soldering the wires to the PSU PCB itself). If I find that there's too much loss or if it becomes a problem later, I will change it. But I'm getting a strong 12V, -12V, and 5V at the logic board so I think it will be ok. I have two peripheral cables (4pin molex) also going out the original holes for those cables, but note that I opted not to go all out and reuse the original connectors. The lower left corner of the picture has the original harvested relay from the stock PSU that will drive the passthrough power port (for monitors, etc). It is driven by 12V and will provide passthrough power only once the PSU has turned on. Works great. The Corsair PSU is held on by new stand offs I put in place. I drilled four holes and mounted the stand offs and then mounted the PSU to it. For the PS ON signal, I'm doing the usual transistor based inverter solution. There was some rust on the original metal PSU enclosure. Evaporust got it all off. There was some pitting of the metal but it's ok. I put new zip ties on for the grab handles. The original zip ties Apple used had gone brittle and were crumbling so I replaced them. There's a 120mm Noctua fan installed. Yes, it might not provide as much air flow as the stock fan, but it's still pretty strong. I have the old fan in case I need it but appreciate the lower volume of the Noctua. Here's the other side of the reassembled PSU with the cables. PSU works great! I just need to figure why I'm getting a loud pop from the speaker before the chime plays each time I cold start the Quadra. I printed out the schematics @Bolle generated for his Quadra 950 reloaded project on github. Looking at the speaker area now to see if any of the blocking or decoupling caps have gone bad. They are ceramic SMD caps. Pulling them off one by one to check them.
Posted by: jmacz on 2025-09-12 17:12:36 Spoke with Bolle and he mentioned the quadra 950s he worked on all seem to have this pop from the speaker before chime. So it sounds like a common issue. In that case, I'm not going to worry about this now.
Posted by: jmacz on 2025-09-15 21:12:13 Quadra 950 is done... that static pop immediately on power on (before chime) is annoying, wish there was something to be done about it. Feels like some unexpected noise going to the speaker on power on before everything has stabilized. Maybe needs something to keep the speaker down until a split second later before the chime. Anyhow, the reset and interrupt buttons were broken when I received this 950. So modeled my own. Tried 3D filament printing them but the icons on the top are too detailed so switched over to 3D resin printing instead. Here is the result: Works well. The logic board retainer was also completely broken off and missing. I needed something to hold the logic board in place so put a little clip together (the three white blocks in the picture): And the final result: Finally set of changes: Broken interrupt button switch - replaced it with another push button switch. Replaced broken reset and interrupt buttons with 3D resin printed replacements. Epoxied two broken feet back together. Removed rust on internal metal shields and power supply housing. Replaced dead power supply with converted Corsair HX1200 ATX power supply. Filled all VRAM slots with new VRAM modules. Fixed as many broken plastic pieces as possible but not everything could be saved.
Posted by: is2scooby on 2025-09-16 13:00:37 Wow, it looks like it’s 1992 all over again in that picture!
Posted by: jmacz on 2025-09-30 20:17:28 Only issue however is that on a cold boot, before the chime, I get pop from the speaker (and headphone jack) before the chime plays. Only happens on cold boot, restarts are fine. After that the audio plays fine including the chime. I don't think this pop is normal. Trying to figure out what it is... I just need to figure why I'm getting a loud pop from the speaker before the chime plays each time I cold start the Quadra. I printed out the schematics @Bolle generated for his Quadra 950 reloaded project on github. Looking at the speaker area now to see if any of the blocking or decoupling caps have gone bad. They are ceramic SMD caps. Pulling them off one by one to check them. Spoke with Bolle and he mentioned the quadra 950s he worked on all seem to have this pop from the speaker before chime. So it sounds like a common issue. In that case, I'm not going to worry about this now. I was watching a video of a Quadra 950 boot and it doesn't have the loud speaker pop on boot. So not sure what's going on. Need to disassemble it and debug as it's just bothering me at this point 🙂 I believe @Bolle mentioned the units he had were doing the same thing so there must be something that goes bad on these units over time maybe? Another thing for the to do list.
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