Quadra 950 Not Booting

[tt]

If you have a scope or a meter capable of measuring high frequency, then check pin R7 and R9 of the 68040 to make sure the clock signals are going. If you don't have a scope/fast meter, measure those pins in voltage mode to make sure it is not almost 0V or almost 5V. Basically, a value in between suggest a changing signal.

I have a 2 chan PicoScope that goes up to 50 MHz, might not be capable enough. Thanks for the detailed instructions on the signals to check on. Could I also check the crystal's pins for a more direct measurement?

Measure the ohm of the speaker to make sure it is not open or shorted. I assume you've given the computer plenty of time to boot or show video, and haven't given up too quickly due to a lack of chime.

I mostly use compact Macs, so when I initially fired this machine up, I had it connected to an LCD monitor with an adapter with the dip switches. I wasn't getting any signal and I have used it before with (I think) a IIci. To be more conclusive, I would need to dig out an Apple monitor and try that assuming that works. I feel like this hardware has gotten to an age where almost everything has an issue, even if I have done some maintenance to it in the past 5-10 years. I did try another test speaker to see if there was an issue with the original one.

 

[joshc]

Any sound if you plug in headphones?

Might be worth seeing which other chips are getting hot other than the CPU.

 

[tt]

Any sound if you plug in headphones?

That's a great idea, I haven't tried plugging into the 3.5 mm jack. I had to put the machine aside to work on another project, so I'll get to it in a bit.

 

[joshc]

Have you given up troubleshooting? Just noticed your trading post asking for another board.

 

[tt]

I haven't given up, but for a couple reasons I thought I should look for another board. I have some events I need to prepare for the next couple weekends, so I had to tuck away the behemoth to keep it safe.