ROM or not to ROM?

[sonic84]

Hello, I was given a PowerMac 8600 to fix up. It's not making a startup chime or putting out any video. I found the ROM slot is empty. Does anyone know if this model had a built-in ROM or was the ROM on the removable SIMM?

 

[Fizzbinn]

I believe its most common for the ROM slot to be empty in favor of soldered on logic board ROMs (on the bottom of the logic board) but it is possible you have an early? model that shipped with a ROM SIMM.

What are the other symptoms? Power LED/Fans turn on, drives power up?

You might try cleaning the edge connectors of all RAM and VRAM DIMMs with a pencil eraser and/or applying some Deoxit D5 to the slots.

Have you checked the Apple Service Source docs troubleshooting section?

https://macdat.net/files/pdf/apple/servicesource/powermac_8600-9600-ws9650.pdf

 

[sonic84]

good call! I took a look on the board underside and found the 4 ROM chips were soldered on.
I found out the CPU was dead. It had a MACh G3 upgrade card. I swapped out the ZIF CPU part and it boots now.
There was a gap between the old CPU die and the heat sync. poor thing must have cooked itself?

Thank you!

 

[chelseayr]

could be, considering the cpu itself would be at least 6 to 8 watts so thats maybe not something that likes a pocket of hot air directly!

 

[beachycove]

I had two 8600/300s (604ev) that exhibited this behaviour. This was c. 2003, so in pre-cap-leakage days. Perseverence paid off, i.e., repeatedly re-booting. I think it was some sort of wierd pram issue. Once they started up, both worked flawlessly for years and years.