luckybob wrote on 2024-04-01, 15:22:If you had said P65UP5... I might have believed you.
Don´t mention it, I´m still searching for the PII CPU-card.
There is a part of me that wants to put that card into my p65up8, and then use some socket8/slot 1 adapters just for the giggles.
I really should do some tests with that card. see how Celeron chips work, etc.
Once men turned their thinking over to machines in the hope that this would set them free. But that only permitted other men with machines to enslave them. - Reverend Mother Gaius Helen Mohiam
majestyk wrote on 2024-04-01, 10:12:After threading another wire through it the mainboard came alive again - after three years.
This was quite a journey...
Amazing work - congrats...
Thanks for the props!
Turned out the story wasn´t quite over yet. The IDE1 and IDE2 ports didn´t work.
There was an interrupted trace between "INTRQ" of the IDE1 connector and pin 83 of the PIIX (IRQ14).
On the second IDE port there was a corroded / broken trace between the "INTRQ" pin and a 22R resistor (array).
I think it´s just coincidence that in both cases the INTRQ line was affected.
Everything else seems to work for now, but I will continue testing...
Edit:
While testing all the PCI and ISA slots with different video and soundcards, due to the mechanical "stress" inserting and removing the cards, to original error reappeared. The via that I had repaired lost contact to the inbetween layer trace.
So I bridged the "OE#" input of the tri-state-buffer U16 with a wire to the "SOE#" output of the PIIX (pin 119). Now it´s all stable - again.
I had suspected this would happen, because I hardly got some solder into the totally corroded via the first time.
While everything runs stable now and I couldn´t find any further problems, I found a nice way to replace the original VARTA pest-barrel with a - more benign - 3.6V lithium cell.
To prevent the lithium cell from being "charged" by the onboard charging circuitry I had to "displace" R890 (510R) a little. This can be reverted anytime, if the original state should be desired.
Now I´m happy that this quite rare mainboard could be saved.
majestyk wrote on 2024-04-08, 07:38:I found a nice way to replace the original VARTA pest-barrel with a - more benign - 3.6V lithium cell.
Anyone who owns an old Macintosh will tell you these are not so benign.... 🙁
Yea... those cells are even worse.
The upshot is, its easy to remove and slightly better voltage than a 2032.
So long as you remember to disarm the grenade before putting it back in storage....
Once men turned their thinking over to machines in the hope that this would set them free. But that only permitted other men with machines to enslave them. - Reverend Mother Gaius Helen Mohiam
I have a pair of Apple Quicksilvers since 2002 and the SAFT batteries are still fine. They had to be replaced once, though. Also replaced several in customer Macs - empty, but no damage.
A google search for "SAFT Lithium leakage" returns just pics of healthy cells.
What do these cells do?
well, its not the brand, persay.
But those 1/2 AA cells can just nuke a board: https://www.reddit.com/gallery/kpqaof
Maxell and Varta are the big offenders, but they all have a chance to leak over decades.
I dont trust any brand. I dont leave ANY battery in a computer once it goes to storage.
Once men turned their thinking over to machines in the hope that this would set them free. But that only permitted other men with machines to enslave them. - Reverend Mother Gaius Helen Mohiam
luckybob wrote on 2024-04-15, 20:16:I dont trust any brand. I dont leave ANY battery in a computer once it goes to storage.
I support to strictly abide to this golden rule!
At least the 1/2 or 2/3 AA cells are easy to remove. I use them in cases when the mainboard clock refuses to run properly at 3V (CR2032), even after removing non-necessary diodes or replacing them by Schottkys.
