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Power Mac 6100 PSU Dyna Comp. DCF 803
Posted by: alex-mars64 on 2026-06-16 13:55:25 Hi Mac enthusiasts, I recently acquired a Power Macintosh 6100, unfortunately the power supply is not working. After inspecting it further, I found out, that parts are actually missing, U1 and R1. I cannot find any high res pictures online to get the name of U1 and the resistivity value of R1. If by any chance someone can provide a picture of the PSU section would be highly appreciated! Thanks in advance! Cheers, Alex
Posted by: finkmac on 2026-06-16 14:09:27 those aren't "missing", they're not populated on that board. look, you can see a jumper placed on the lower 2 holes of the DIP footprint.
Posted by: alex-mars64 on 2026-06-16 14:29:33 Hi finkmac, thanks a lot for your feedback! Are you sure this is the case here? The previous owner did soldering at that position, at least it looks like that. Appreciate your opinion! Regards, Alex
Posted by: finkmac on 2026-06-16 16:56:38 that foto would have cleared things up 😆 seems you're right, both these links show that DIP IC: https://pappp.net/?p=65693 https://www.badcaps.net/forum/troub...pply-design/81117-macintosh-6100-power-supply
Posted by: alex-mars64 on 2026-06-17 15:23:50 that foto would have cleared things up 😆 seems you're right, both these links show that DIP IC: https://pappp.net/?p=65693 https://www.badcaps.net/forum/troub...pply-design/81117-macintosh-6100-power-supply Hi finkmac, Thank you for posting the links. Unfortunately the resolution is two low to recognize the IC labeling. Best regards, Alex
Posted by: killvore on 2026-06-18 04:55:32 Hope this helps!
Posted by: alex-mars64 on 2026-06-18 06:09:13 Hope this helps! Hi killvore, Wonderful!! Thank you very much 👍 definitely very helpful! Without your help I would have been stuck with binging it back to life! Have you had issues with the PSU in past? I will replace the parts and see if it works! Cheers, Alex
Posted by: killvore on 2026-06-18 08:10:27 I've been very lucky with PSUs and machines in general, I've only had one bad Q610/PM6100 style PSU and it was dead when I got it. I have a project to fit a Meanwell RPT-160B in the housing since it outputs sufficient amps and fits with room to spare for the original fuse and switch. I'm using the original PCB as a mount. But since I have multiple working PSUs it's not a high priority!
Posted by: alex-mars64 on 2026-07-12 15:17:34 I've been very lucky with PSUs and machines in general, I've only had one bad Q610/PM6100 style PSU and it was dead when I got it. I have a project to fit a Meanwell RPT-160B in the housing since it outputs sufficient amps and fits with room to spare for the original fuse and switch. I'm using the original PCB as a mount. But since I have multiple working PSUs it's not a high priority! Hi killvore, I see. Makes perfectly sense! Thanks to your help, my PM6100 PSU is back to life. Lucky enough the missing IC could be ordered still and be replaced. Additionally one of the Opto couplers was broken. In the end it's running like new! Good luck with your PSU project!
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