G3 B&W processor swap anomaly
 

We've now had two B&W G3s come into the shop in the past two months, exhibiting identical problems, and both with a frustratingly simple solution. No startup tone, no video signal, nothing. I remove all disks, cards, memory, I reset PMU, even took out the battery. No go, nothing. Then I swap the processor (one was an identical processor swap, another was a 350 MHz -> 300 swap), and I get a startup tone but still no video or booting. I reset the PMU again, still no change. I remove the processor, put the original processor back in, and bam, booting and happy. WTF. So anyway, frustration aside, I'd love to hear if anyone else has come across this and maybe we can figure out what's really going on here. TIA!

Maybe it's related to sufficient time without the battery. Try removing the battery and waiting a while, then replacing it.

When you start the B/W with the door open, watch the LEDs. This tells you what's going on. If the LED next to the processor lights, the processor clock is working. Then watch for the 2 LEDs up near the USB ports. If they light, the RAM test and PCI bus tests passed. Now the USB LEDs should turn off to initialize the PCI cards and then turn back on. This is the point that the video should turn on. Now you should see LEDs lighting next to the IDE ports indicating drive activity.

Now, if you get the Processor clock, but no USB, remove the battery and press the PMU switch (The PMU switch never worked very well in the B/W). Give it a few minutes and put the battery back in. This should be sufficiant to get the processor to startup again. For good measure, I would boot into Open Firmware and enter set-defaults, reset-nvram & reset-all to clean up NvRAM.

hayne -- thanks for the tip. I don't think it was the battery, though, because I put the battery back in before swapping the processors, effectively eliminating the battery.

Las Vegas - Good hint! The LEDs were flashing just as you said now, but of course the problem's been resolved. I'd love to see what the LEDs would indicate when the processor is messed. Ditto on the PMU switch--the B&W in my opinion is just in general a bad machine. Oh, and thanks for reminding me to reset nvram--I forgot to do that!

B/W wont start up
 

I have had the same exact problem but like you said i looked on the motherboard next to the usb led lights and they are not on.

I removed the battery. removed all the hardware from the motherboard including the processor and put it all back together and it worked for like 2 weeks after i booted from the cd.... now the cd rom doesnt even work while connected to the mother board...

I would love to know if it might be the processor to much ram bad upkeep or what help!

Although I haven't had the exact problem outlined here (can't actually remember), I do think it was similar. My solution at the time was to remove all the memory and reseat it, remove the processor and reseat it, remove every card and reseat it, and replace the battery. Haven't had the problem since; shouldn't have had it once.

Yea i already did that :( . I took every thing apart. Made sure it all was back in nice and snug and still no go... The thing that really bothers me, is that i had it working again... then a week later I'm back where i started from with no idea what fixed it the first time. I did buy a new battery to replace the old one... and thought that maybe that was what the problem was... because after i messed with the chips a while it started up in OS9 i just fixed witch disc started from and i was off (for a week)... I removed all my ram tried each one by its self so I don't think my rams bad... all 4 chips at once seams kinda unlikely. i even disconnected and tried ether one of my hard drives by them self... ill go ahead and reseat all my chips one more time but I've done it like a lot already.

:D IT WORKED!! first i reseated my ram again and nothing happened but after pulled my processor and bent the heat sink prong down a bit put it all back tight all the leds lit up and a chime I hadn't heard in a while sounded off thanks for all the help! I just hope it'll stay tight this time. :cool:

lol :eek: it all happened after i pulled one of the hd's from the b&w to a friends house (to save the mother-in-laws pc....)

Reformatted it put xp pro on it copied the inlaws files reformatted her comp into working condition then when i go to start up my comp off the other hd i didnt touch...

no tone like what has happened before to this comp it might just be something i bumped loose inside the usb leds on the motherboard wont light up again....

Well i donno even it its worth trying to fix again :(.... just an update...