Dead A600 problem

[Harrison]

I installed a 3.1 rom in my A600 and then the system wouldn't work. The screen remained black and the power and Caps lock lights remained on.

Thinking the 3.1 rom could be faulty I tried the original 2.0 rom back in the A600, but the same thing happened. It won't boot to the kickstart screen indicating the system is hanging before or during trying to load the kickstart rom.

At the suggestion of Zetr0 I've just tried the 3.1 rom in an A500 and it sort of works, but with some strange behaviour. When the A500 is switched in the power led flashes and eventually a red software guru message appears, and then the system reboots and the 3.1 insert disk boot screen appears. So the 3.1 rom seems to be working. With some investigation I found out the this behaviour can is due to certain revisions of A500 not being able to handle the 512KB kickstart rom (it can't load the last 256KB from the chip due to the way the socket is wired). Is that correct?

I also discovered that with the 512KB trapdoor expansion removed the A500 with the KS3.1 rom wouldn't work at all. I would just keep flashing the power led and nothing displayed on the screen. But replacing the 512KB trap door expansion (1MB total ram) the A500 started up, guru'd as before and then went to the 3.1 boot screen.

However I did try booting a Workbenchh 3.1 disk in the A500 and it loaded Workbench completely, but as soon as I tried to select the About menu item the system hung with an 80000004 software error. Any ideas? Faulty ram? Or faulty kickstart 3.1 chip?

At least it did prove the chip kind of working in the A500.

Sadly that seems to indicate the A600 could be dead.

I'm going to try the A600's original rom in the A500 next and see if it loads that correctly. I might also try the A500's 1.3 rom in the A600 to see if I get any success with that combination.