Power Computing PowerBase & PowerCenter Boot issues

[macinbot]

I've got a few Power Computing machines I need help troubleshooting.

None of them seem to want to boot. I get no start up chime or video output from any of the machines.

I have two PowerBase 180 machines and a PowerCenter 120. The PowerCenter has booted without issue in the past, but has been sitting for a couple years unused (climate controlled). The PowerBase machines I acquired without knowing their boot status. This is first time I've tried to revive them.

They all power on. All do a cursory power-on poll of the CD-ROM. On power up, PowerCenter will poll the hard drive. The PowerBase machines don't seem to do that, but that may be an IDE thing?

Things I have tried:

• Reseating all the cards including processor card, PCI riser, cache, and ram
• Pulling all ram and using known working ram from PowerMac 5400 (is there a preferred single ram slot?)
• New 3.6v battery installed
• Reset CUDA switch
• Used both Apple Performa Plus 640x480 DB-15 display and VGA monitors
• Cursory examination doesn't show any obvious signs of capacitor failure

What next?

 

[MJ313]

These machines can have cache modules that go bad for whatever reason. Try removing the cache and booting without it; it's a relatively easy thing to rule out.

 

[macinbot]

I'll give it a go and report back.

 

[macinbot]

The PowerCenter and one of the PowerBase machines had a cache module, the other PowerBase did not. Pulling the cache on the two machines made no change in starting up. I also swapped the cache into the other PowerBase just to rule that out, and it also made no difference.

 

[macinbot]

Tried using an replacement ATX power supply to see if that made any difference. It did not.

Very open to suggestions.

 

[macuserman]

I had a similar experience on my PowerCenter and it turned out to be a bad rom I believe.

 

[macinbot]

Well hmmmmmm. These machines are outside of my interest vs investment ratio. I think its time to move them on to someone who has more drive to restore them.

Appreciate the reply.