LC575 computer killed LC520 motherboard! ðŸ˜
- Thread starter JDW
- Start date
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- color classic lc520 lc575 repair
Oh no doubt some of those 575 body pins may have turned green. I pulled one of our office G4 Cubes from storage a week ago, and when I pushed in the handle and pulled out the core, I noticed that the soft metal mesh that goes around the top edge of the core and makes contact with the inner metal body had mostly turned green.
My 575 body was never purchased to be used, really. My friend @Kay K.M.Mods tipped me off about a Yahoo Auction not long after he first supplied with the the Color Classic. I won the auction for ¥9250 (about $60 at today's exchange rate) which included domestic shipping in Japan. The purpose was to get its motherboard. $60 for that board is "only reasonable" in my opinion, but EBAY prices these days show it to be a steal. The machine functioned initially and I showed that in my early videos. It worked most likely due to the fact the motherboard had never been removed and left removed. But after I removed it and put it in my CC body, I never put anything back inside the 575 body. So after a few years, I can see how oxidation and green crud may have grown on the motherboard contacts inside the body.
That green crud is nasty stuff though. It's in my SE/30 connectors too. Or at least it was. I used DeOxit D5 to get rid of it in the past.
Oh, and if you want to see how the high humidity, hot summers and cold winters of Japan wreak havok on vintage Mac LCDs, take a look at what has happened to G4 Cube monitors put in our office storage...
15" Display
22" Apple Cinema Display
It's the so-called "vinegar syndrome."
I really lack time and patience to figure out of a panel swap would be possible to fix these. It's just so sad.
My 575 body was never purchased to be used, really. My friend @Kay K.M.Mods tipped me off about a Yahoo Auction not long after he first supplied with the the Color Classic. I won the auction for ¥9250 (about $60 at today's exchange rate) which included domestic shipping in Japan. The purpose was to get its motherboard. $60 for that board is "only reasonable" in my opinion, but EBAY prices these days show it to be a steal. The machine functioned initially and I showed that in my early videos. It worked most likely due to the fact the motherboard had never been removed and left removed. But after I removed it and put it in my CC body, I never put anything back inside the 575 body. So after a few years, I can see how oxidation and green crud may have grown on the motherboard contacts inside the body.
That green crud is nasty stuff though. It's in my SE/30 connectors too. Or at least it was. I used DeOxit D5 to get rid of it in the past.
Oh, and if you want to see how the high humidity, hot summers and cold winters of Japan wreak havok on vintage Mac LCDs, take a look at what has happened to G4 Cube monitors put in our office storage...
15" Display
22" Apple Cinema Display
It's the so-called "vinegar syndrome."
I really lack time and patience to figure out of a panel swap would be possible to fix these. It's just so sad.
With the 3 resistors still soldered to the board, I wanted to re-run TechStep again. All tests passed this time, including SCSI. When I pressed zero (0), it told me my spinner drive's make and model number. So all good on that front. Later testing will be done with the 3 resistors removed, and then with ROM and VRAM SIMMs put back onto the board.
Boy, I really am grateful to you, @David Cook !
Boy, I really am grateful to you, @David Cook !
From your expression of concern at the start of this thread, I related to how you felt about being the possible cause of damage. We've all been there. The logical side of us knows that these old things are going to break once in a while, and that we fix more than we harm, and that it is better for a machine to be loved to death than decay in a landfill. Nevertheless, we never want to feel like we were the cause.
In this case, a happy ending. Not only did we discover that the board remains in fully working condition, but the community now knows how to 'save' related boards.
Glad to be with you on the journey.
- David
@David Cook
To bring this thread to a final conclusion, I just wish to say that after removing the 3 resistors again in order to overclock back to 33MHz, and with my VRAM and 32MB RAM SIMMs installed, the motherboard booted up right away inside my Color Classic, and its currently running Norton System Info just fine.
So it would appear that a mere cleaning of the GOLD contacts of the motherboard's main connector is now something everyone should do, even when you've confirmed boards working rather recently, as I did. Mine suddenly stopped working, and I thought the worst about the LC575 body. That body clearly is dead (probably faulty caps on the Analog Board, as I never replaced those), but because I am focused on the Color Classic body, now that it's all working again, I only have you, David, to humbly thank. I am especially grateful that you didn't give up on me, and kept brainstorming all the way through. Had you given up on my early on, I'd still be sitting with a non-functional board. So when I say THANK YOU, I sincerely mean it from the heart!
LC500 and Color Classic owners, clean those motherboard connectors!
Best wishes to one and all!
To bring this thread to a final conclusion, I just wish to say that after removing the 3 resistors again in order to overclock back to 33MHz, and with my VRAM and 32MB RAM SIMMs installed, the motherboard booted up right away inside my Color Classic, and its currently running Norton System Info just fine.
So it would appear that a mere cleaning of the GOLD contacts of the motherboard's main connector is now something everyone should do, even when you've confirmed boards working rather recently, as I did. Mine suddenly stopped working, and I thought the worst about the LC575 body. That body clearly is dead (probably faulty caps on the Analog Board, as I never replaced those), but because I am focused on the Color Classic body, now that it's all working again, I only have you, David, to humbly thank. I am especially grateful that you didn't give up on me, and kept brainstorming all the way through. Had you given up on my early on, I'd still be sitting with a non-functional board. So when I say THANK YOU, I sincerely mean it from the heart!
LC500 and Color Classic owners, clean those motherboard connectors!
Best wishes to one and all!