Repairing a Beige G3 Bomb Victim...

[EvieSigma]

The beige G3 DT I got (300MHz with Zip drive) was sadly the victim of a battery explosion...the explosion damaged the logic board beyond repair, torched the VRM, and left a huge rust patch on the swing-out drive cage. I'm in the process of cleaning up the rust and putting together a list of parts I need to make this machine run again...so I figured I'd start by asking the wise minds here at MLA for some help.

Here are some photos of the ROM SIMM, it wasn't directly in the path of the battery explosion but it looks like it did get a bit messed up...is it too far gone? I honestly can't tell myself.

https://i.imgur.com/UOreU3s.jpg

https://i.imgur.com/OXdx8fN.jpg

Also, while they seem to still be intact, the little white connectors that plug into the motherboard do seem to have a little bit of corrosion in them. What should I use to clean them up? A dip in vinegar or something else?

 

[Unknown_K]

Guess you will have to try the ROM and see, clean the edge contacts with a soft pencil eraser before you do.

 

[EvieSigma]

Is it safe to dip the little connectors in vinegar though? I know there's contact cleaner you can get from the auto section of your average retail store, but I dunno if that stuff cleans up light green corrosion like vinegar does.

 

[EvieSigma]

I have the machine running but the CD drive is proving to be problematic. I hear it spinning (it's rather loud actually) but even after cleaning the laser it doesn't read disks and the green disk access light never lights up. Dead drive?

And if so, can I use non-Apple branded drives like on a B&W G3 or is the beige restricted to Apple drives only?

Also, how do I set the CPU speed jumpers on the motherboard?

 

[EvilCapitalist]

I had an Apple drive that would spin up a disc (loudly, like yours) but it couldn't read any burned CDs and could only read standard pressed CDs very slowly, if at all (it usually failed out with read errors).  When I replaced it with a non-Apple drive I had issues when I tried to boot from a CD...namely that the machine refused to do so.  Once the machine booted it read things just fine but I ended up swapping it out for an Apple branded one all the same.

You'll want to read the article Low End Mac has on the Beige G3 jumper block.  You'll have to take out whichever color coded one your machine came with and then use a bunch of individual jumpers to set the bus speed and multiplier.

http://lowendmac.com/1997/overclocking-beige-power-mac-g3/

 

[EvieSigma]

Are they standard sized jumpers or no?

 

[Unknown_K]

They are the size used on 68 pin SCSI HDs. 2mm instead of 2.5 or something like that.

 

[EvieSigma]

Oh...that's unfortunate, the only jumpers I have are standard sized ones. Guess I'm stuck at 266MHz for now, I should have taken the jumper block off the old board before I trashed it but it was so toxic-looking that I didn't really want to touch it...