faulty a500 testing...

[Azryl]

Paula and the CIA's do all the glue logic for the floppy drive and DMA sections to the memory bus. So your incorrectly inserted floppy header most likely did damage to Paula, Odd and Even CIA and probably Gary as well.

So you will need to buy/find/steal some extra CIA's so you can check Odd and Even with new reliable known working chips. Then Paula, lastly swap  Gary.

If the mobo still fails to boot....  buy an A3000

Az

[Azryl]

Oh, there is the possibility that the miss-aligned power pins ( 12v + 5v ) did damage to some of the resisters/diodes at the Floppy port....  not sure of the procedure to check these.

Hope someone with more hardware knowledge gives a hint!

Az

[AmmoJammo]

So your incorrectly inserted floppy header most likely did damage to Paula, Odd and Even CIA and probably Gary as well.

So you will need to buy/find/steal some extra CIA's so you can check Odd and Even with new reliable known working chips. Then Paula, lastly swap  Gary.

:idea:

yes it had a faulty odd cia, its been swapped for a known good one, ALL of the socketed chips have been.
 

[djos]

AJ I'm likely to have some spare CIA chips and maybe a spare Gary shortly if you need them.

[danbeaver]

This technique requires a scanning thermometer (about 30+ US salad leave or)  borrow one. Powered up good chips generate heat; the amount varies, but a dead chip is as cold as background non-chip components or are hot as hell from a short (usually does not last long, can you say "blue smoke?")

[AmmoJammo]

I discovered my "good" amiga displayed the same issue when I swapped out the CPU and kickstart rom...

I think from memory, it was the CPU not being seated properly that caused the issue then...

however, the "bad" motherboard still doesn't work?