PowerMac G5 Dual 2.0 Chimes but no video

[hackerwayne]

Hi all 🙂

Just received a old PowerPC G5 2.0GHz Dual Processor. When i tried to power it on, the Power LED came on as usual and the G5 chimes, but it didnt display any video on the screen. 🙁 None of the diagnostic lights display red, heres what i've done

- Reseated all the RAMs
- Pressed the PMU button
- Tried CMD+Option+P+R but didn't hear a second chime
- Swapped a good working graphics card
- Swapped a good working display with good DVI-D cable
- Tried CMD+Option+O+F my LCD idle light flashes from amber to green but after 2 sec back to amber (idle)
- Tried holding down power button for 5 sec and heard a tone sound + LED light flashes
- When i took the plastic cover off 1 Diagnostic LED turns red and the fan starts to run at full speed (which is normal)
- The fan runs at normal speed if the plastic cover is in place.
- HDD is detached but same issue when the HDD is in place.

Not sure if the internal CMOS battery is still good, but i don't think it will cause such issue right?

 

[photonorm]

overheating?

Are there any other LED lights deeper into the computer that you can see on when you are looking into it from the front? There is a LED that will come on when the processors are too hot. I am experiencing the same symptoms you are. However, I am working with a Dual 2.5 that is liquid cooled. I just did my second rebuild of the LCS and I can't get past the chimes and the overheat LED comes on.
If your machine is liquid cooled check for any coolant leaks.
I look forward to your future postings as we might be in the same boat.

You can read about my original situation at https://forums.macrumors.com/threads/1109014/

-Norm

 

[havokalien]

2.0 not liquid cooled

Try unscrewing and switching the processors. If it boots then one of the processors is dead. You will need ASD 2.5.8. Email me and I can help you there, I may even have a spare processor.

 

[hackerwayne]

Are there any other LED lights deeper into the computer that you can see on when you are looking into it from the front? There is a LED that will come on when the processors are too hot. I am experiencing the same symptoms you are. However, I am working with a Dual 2.5 that is liquid cooled. I just did my second rebuild of the LCS and I can't get past the chimes and the overheat LED comes on.
If your machine is liquid cooled check for any coolant leaks.
I look forward to your future postings as we might be in the same boat.

You can read about my original situation at https://forums.macrumors.com/threads/1109014/

-Norm

Thanks for the heads up, no over temp LED lights up. Everything is absolutely normal (Chimes, does PMU reset) except no display and doesn't do PRAM reset

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Try unscrewing and switching the processors. If it boots then one of the processors is dead. You will need ASD 2.5.8. Email me and I can help you there, I may even have a spare processor.

I do have some spare 2.3GHz processor around. (My side line is to repair, refurb and resell used/old Macs), not sure if they are compatible, but when i plug it in, Processor A and B Over Temp message came on (at this point, im 70% sure they arent compatible) but when i switch the 2.0 back, no LED lights up. Tried removing A and let B runs, vice versa. No dice. Currently the unit is still in my store room so i can do any kinds of test.