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zezba9000

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  1. Here is the stuff I used. The solder core with that rosin work way way better than what came with the solder iron. Before you apply the rosin, dab some 99% Isopropyl Alcohol to clean off the area, then dab some rosin paste on the area and apply some solder before setting the cap. Also make sure to use the super fine point tip on the solder iron. Solder Iron: https://www.amazon.com/gp/product/B014KBIB Rosin Paste Flux: https://www.amazon.com/gp/product/B008ZIV85A Rosin Core Solder: https://www.amazon.com/gp/product/B00030AP48
  2. #1 I ruled out buy connecting the caps from the working board to the non-working one with some wire clamps. The CPU being as hot as it is is going to be fine when idle. Under load for a long period of time it may not be (as is the case with ARM chips in your phone etc). My concern is these computers have been around for a very long time and the one I got that doesn't work was very dusty which can increase the CPU temperature even more and if someone left it on under stress for a long time it could cause damage as these old computers don't have auto power off when the CPU gets to hot (if you get yours working again, I would put a heat-sink on it). When a CPU goes bad it can still partially work but then fail when it starts to use other parts as not all circuits will just stop functioning. The other possibility is the original PSUs in these damage something else on the motherboard. Both PSUs in the working and non-working IISI computers were leaking some fluid on the board and both PSUs had issues. If the original PSUs were this bad, maybe a bad CAP in them caused a bad power fluctuation on the motherboard and damaged a chip when going out. My hope is it damaged the CPUs crystal oscillator and the reason I think I could be on the right track is the CPU in the bad computer gets much hotter much faster than my working one. I'm moving soon, so my on and off tests with this may slow for a month or couple of weeks. Just FYI.
  3. Also just a tip. If you need to convert an ATX 20-pin to a 10-pin you can also just use a PICO PSU to embed the PSU directly into the Macintosh computer as they're super small. Something like this would work: https://www.ebay.com/itm/12V-180W-DC-Pico-ATX-switch-PSU-with-Power-Adapter-Car-Auto-MINI-ITX-Power/263087650726 For a CPU heat-sink, get the same ones used for ARM A20 (they're the perfect size [tested]): https://www.ebay.com/itm/Heatsink-for-Cubieboard1-Allwinner-A10-Cubietruck-Cubieboard2-A20-heat-sink/231904141192
  4. Did a quick clean of the new motherboard. Everything works except for the scsi. I know the hard drive and cable are fine as it came from a working computer. Might need to replace the caps if thats the issue.
  5. Made some directions for making a Macintosh IISI PSU very quickly. Based on a YouTube video but simplified. 1) First buy one of these "24 Pin to 10 Pin" off Amazon or Ebay: https://www.amazon.com/gp/product/B07C5P5H2L 2) Rewire it with the image below. More info and reference files: https://1drv.ms/u/s!Alt5wRhQYKD7gd4qoWijVukp9uDeOg YouTube video this is based on: https://www.youtube.com/watch?v=CNerj2mQ4vw
  6. Ok just got another Macintosh IISI motherboard. It works perfect with my custom ATX PSU! Still need to wash the motherboard but its sound is still strong so caps seem still ok. The custom ROM SIMM doesn't solve the problem on my old board (so ROM SIMMs are not the issue). But now I can compare some stuff. The new one has all black memory slots and doesn't require a SIMM. The old one requires a SIMM with all white ram slots. So first thing I noticed and was looking for was CPU temperature. Why? Well both ROM SIMMs chime sounds load (stock and custom) but then the board just hults. Disk drive doesn't register or anything else on the board. This makes me think a couple things (which I will try as time goes on). #1) The large dark blue caps close the the floppy disk drive might be bad which could be causing something else to fail on the board. #2) The CPU get very hot on these... to hot for my liking. Normally CPUs that get this hot usually need a heat-sync when under heavy use. (comparing to RaspberryPi etc type systems). The CPUs might be burning out (So I will put a heat-sync on my working board). Pretty sure all my other macs without heat-syncs don't get hot at all. #3) My bad boards CPU gets hot much faster than the working CPU. Its possible the crystal oscillator that controls the CPU clock may go bad on these computers... and the oscillator after a time could be its under some kind of temperature stress from the CPU not being cooled properly. IDK if 1-3 are valid ideas yet but will try to knock out and validate some of them. Images below show off the new working one and old broken one.
  7. Still waiting on other motherboard (which has black memory slots). Just got the custom ROM SIMM in the mail today so haven't tested yet. Will report back once I do.
  8. That would be nice if there is a General category form area? Create and link it.
  9. One other note. Waiting for mail. Got a custom ROM SIMM from BigOMessOfWires to see if a custom rom skips some error the stock one is having. Also got another motherboard from Ebay that doesn't need a ROM SIMM to see if I can get that one working.
  10. I didn't find any traces I could see. Did a test of leaving it on for 30 min to see what chips get hot or warm. CPU seems to get pretty hot when you leave it on doing nothing. Not sure how hot a working one gets when its left on. If they don't normally get hot that might be an indication of something idk. Wondering if the original PSUs in these could have blown out stuff on the motherboard when going bad. The Hard Drive that came with the computer doesn't spin up. Maybe a power surge. Just a thought. I wonder if the CPU oscillator is bad? Also when you put a ROM SIMM into your IISI was it a custom or stock one?
  11. I'm also open to some type of group action (I just want my stuff back or him to respond or update his site to explain delays). Whats the best way to deal with this. Give him a group warning that we will be reporting fraud to his local authorities or what? What is the normal or best way to deal with fraud of this kind? Because he has had so many peoples stuff without replaying ... this is borderline theft at this point. I'm sure we all have our email chains with him backed up for evidence of fraud.
  12. @9166188 Did your motherboard have a ROM SIMM? Mine does which I read was rare. Wondering if yours is the same? If so wondering if the versions with ROM SIMMs have this issue.
  13. So I converted an ATX PSU to work with the 10-pin Mac PSU type. The computer powers on but has the same issue. At least I know its not the PSU that causes this issue. I might post back with good instructions on how to convert an ATX PSU to work with Mac II(SI/CI). Its pretty easy if you have the right stuff. (Much less work if you get a part off Amazon or Ebay).
  14. I'll post back here if I get any response from him.
  15. So I've decided to try and use a normal ATX PSU using one of these adapters (24 Pin to 10 Pin Power Supply ATX PSU Adapter Cable): https://www.amazon.com/Asicminer-Power-Supply-Adapter-Cable/dp/B07C5P5H2L I might need to swap some wires, not sure until I get it but seems like a logical test. If I can get it to turn on using a normal ATX PSU I can at least confirm a PSU vs motherboard issue and make better choices from there.
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