Power Macintosh g3 All in One Beige boot problem

Have you checked the battery voltage with a multimeter? With some Macintosh models, a low battery voltage could lead to unexpected problems, including startup difficulties.

I vote with Jan. I have two Beige G3s and they are the most dependent on a fresh PRAM battery of any Mac model. They put great dependence on that battery. I've had batteries that failed in starting a Beige that would work perfectly in older Macs that placed fewer demands on PRAM.

However, your can get around a dead battery if you have the system disks that came with the computer or some utility like Disk Warrior or TechTools that shipped with a bootable CD. Start the computer from the CD by holding c while booting and, once you get a desktop, warm boot from the hard drive. Should start up. Once started, make sure power doesn't get cut to the computer until you get a fresh battery. As long as it's plugged in it should keep working.

Batteries are expensive from a retailer like Radio Shack (nearly US$20) but cheap if ordered online:

https://eshop.macsales.com/item/NewerTech/BAA36VPRAM/

When my Beige G3s were the money-maker workhorses of the home office, I kept spare batteries in the frig and changed them once a year whether they needed it or not.

Also, if I got this thing to work again, how much do you think I could sell this thing for, with a keyboard and mouse?

As the computer can't officially run a Mac OS version newer than OS 10.2.8 Jaguar and shipping on the AIO model is high due to the weight, I think you'd be lucky to get US$20 for one today. Here's one on eBay for US $30 with no bids:

http://www.ebay.com/itm/Vintage-Apple-Macintosh-M4787-PowerMac-G3-Molar-All-In-O ne-For-Parts-/252542920890?hash=item3acc…

Do you have access to another ADB keyboard that could be tested? Any signs of leaking capacitors or discoloured electronic components on the logic board? As you know already, the logic board section is accessible via a tray. However, all work in other sections of the computer is very dangerous (high-voltage circuits; charges can remain for a long time even after the computer has been switched off and disconnected from the mains) and only for qualified personnel.

This is turning into a pleasant walk down Memory Lane!

Have you tried powering on using the button on the computer case?

Not sure about the Beige AIO (nicknamed "The Molar" because it reminded someone of a great tooth) but the mini-towers had a rather flimsy mounting system for the case-mounted power button. After some use, the plastic mounts that held part of the switch assembly would flex too much when the user depressed the button. The result was the contact did not remain closed long enough to get a proper start.

The button assembly on the mini-tower was easy enough to access and you could add support to overcome the problem. However, this issue did not prevent the computer starting from the power switch on the keyboard, thus raising the the ADB keyboards questions Jan and I posted.

Have you removed any PCI cards that came installed? If not remove any in the three PCI slots but leave the card in the longer inboard slot (more below).

Tried a CUDA reset? Press and hold the CUDA rest button for 20 seconds. I'm not sure that this will help as the old battery was surely long ago drained but, if the dying battery corrupted the contents of PRAM, the CUDA reset clears it all.

Is the Personality card is properly seated? They work loose with age and vibration and can cause a failure to start. It lives in the PERCH slot inboard of the three PCI slots. Remove its retaining screw and completely remove the card. Clean its contacts and blow out the slot. Reinsert, then remove and insert again to freshen the contacts. This card must be level across its entire length and it take some force to accomplish that.

I remembered one bug in that series: the voltage regulator, located near the PRAM battery cage. One brand, "Royal," was clearly not up the the job and its failure could give the symptoms you are seeing. The brand is clearly marked. If Royal is not clearly visiable, then the regulator is not the problem

I don't know if you have one but here is a logic board diagram, from the MacGurus website:

http://www.macgurus.com/products/motherboards/mbppcg3allone.php

There is also some lovely information contemporary with your computer that is useful.

Drat! I thought a loose Personality card would be the secret sinner! I'm running out of ideas.

Let me noodle on it s bit longer.

Got a 1Ghz G4 CPU upgrade running on my original 266 Mhz G3 and it is running OS X 10.3.9 Panther.

I got that Mac stuffed with a 64 GB Ati Radeon video card, USB 2.0/ FW 400 card and a Gigabit Ethernet card with the full 756 MBs of RAM.

That Mac ran great for years until I switched to a real G4 PowerMac Mirror Drive Doors model back in 2003.

I still have it!

Not good for games, has limited web browser ability now as content creation has changed, but still boots and works fairly quick for a 20 year old Mac.

I miss these kinds of affordable, upgradeable Macs.

These were a lot of fun to use and upgrade back then.

I wish it could be more useful in today's more modern computing environment.

😉😟😢

I, also, still have older upgrades for my beige G3 still carefully packed away.

Another examination of the logic board with a magnifying glass? Leaking/bulging electrolytic capacitors and other damaged electronic components can be difficult to detect.