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BGE's take on the Quadra 900/950 ATX PSU Mod

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On 9/15/2020 at 1:04 AM, BadGoldEagle said:

Also, I have been trying to calculate the LB power consumption... I'll probably create a new thread about this but here's where I'm at:


I'll see if I can dig up testing I did as part of my project later. I did some tests as part of current draw/voltage drop across my board by making a harness to go between the motherboard and PSU with breaks in the voltage lines. Hooked up my bench PSU as the power source to get a fairly accurate idea of current draw on 5V and 12V, as well as a measurement of input voltage vs output voltage (aka, does my board need thicker copper and/or thicker traces/more plane area?). I mostly just shat pictures into a group chat instead of actually documenting anything, which makes it difficult. Go me? I should be able to find stuff on the IIcx, IIci, IIsi, Quadra 650 and LC 3. Having charts of the various Apple machines and real world power draw would be nice. 

Edited by Compgeke

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Sorry for the lack of updates, I've had stuff to do at work and my 950's system folder got corrupted. I only now realized that I had a spare HD with 7.6 on hand... So I was able to re-bless my 8.1 Folder using 7.6. 

I'm currently imaging that hard drive. It has some pretty rare programs and extensions.


This also gives me the opportunity to test the QuadrATX. So far, everything works, the system is stable. I'd like to test some Nubus/PDS cards but for that I need a working FDD (I have a second Floppy EMU on the way as my original one is in a different country).


Also, in my last post, I had noticed that the fan controller was acting up sometimes. If you didn't give it enough time in the ACC position (key to I), the fan would only start 30% of the time. After a simulated power outage (and the key in the lock position), it wouldn't start up at all. Well today I tried another bootloader, and my Attiny85 quit working altogether. So I used one of the ATtiny25s I ordered for you guys and flashed it with my code. Now the fan works correctly 100% of the time. I got the Attiny85 on eBay (I bought the 25s on Arrow), so that may be why it died...



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On the menu today: Endurance tests with PDS/Nubus cards.

I don't have that many (1x Supermac PDQ, 1x Ethernet and 1x Houdini II DOS Compatibility PDS card, currently testing the latter).


Apparently PC Setup 1.0.3 works fine under 8.1... It shouldn't but it clearly does. I've never been able to load the control panel let alone start the PC using 1.5.4/2.1.7.


It's slow as hell (according to my calculations, preparing that 2GB drive file should take about 76 minutes...) but it's working!


Edit: It took one hour and 28 minutes. My estimation wasn't that bad after all.


Edited by BadGoldEagle

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