Confusing Cube

[Strimkind]

Some of you on IRC have heard this story, but I need to reach a larger audience.

A while ago I got a G4 Cube with a 17" ADC monitor. Initially it was being weird when it was on by randomly turning off. Since I was busy moving, I didn't have time to investigate it further.

After moving I was finally able to set it up. When it started up it worked fine on the ADC monitor, but on restart it refused to show anything on the LCD. I found time to open it up and hit the CUDA switch. Figured that while I was in there I would install an airport card and another stick of RAM to fill the 3rd slot.

Reassembly resulted in power up but no video or audible booting.

Opened it back up, removed the RAM. Same thing. Removed the Airport card, and it booted!

Now there is a noticeable lag on boot before any OS 9 extensions have loaded. Once loaded, it seems fine. Put it to sleep, it starts back up no problem. Restart it...uh oh. Can't restart. It has power but the HD shut off and the unit shows no video or anything. Its stuck.

Have to pull the Main Power.

Boots back up, changed monitor in case the PSU is weak, to a VGA. Nothing changed. Oddly it turns off when shifted from its side to upright (no it was not on the side the whole time, just while I checked the firmware).

Alright, wtf.

Updated to 9.1, firmware is up to date, reset NVRAM, PRAM battery has been pulled.

Where to go from here? Should I go after the CUDA again? Change out all the RAM?

I really hope I don't have a dud for a cube.

 

[Byrd]

By all means try the simple stuff first - reseat/replace RAM, reseat CPU card, airport card (+ harness), and make sure the Cube has a good PRAM battery.

If this fails, the random switching off could be due to a faulty reed switch (the touch sensitive power button); this is a common issue and I recall Cubeowner forums suggesting some simple fixes. If this fails, it could be the VRM, so you might want to check the lines with a multimeter in this instance.

JB

 

[techknight]

If moving it causes a shutdown, sounds like bad connections. If it isnt the power switch, its going to be either bad solder on one of the BGA ICs, or possibly wire shorts, or something stupid like this? im willing to bet bad solder on the BGAs that constantly get hot/cool, causing fractures.

 

[H3NRY]

PRAM battery is pulled, as in you don't have one? That would account for a lot of random weirdness. You NEED a good battery in a Cube. Random shut-offs and turn-ons are likely related to the proximity sensor on-off switch. Much discussion on forum at cubeowner.com, but generally cleaning & flipping over the gasket around the button will make it behave. Other problems could be bad RAM, but that's more often crashes while launching programs or booting. The Airport card sounds suspect, or perhaps the socket for it has a bent pin. Other wise, make sure all cables and cards are firmly seated, etc. Normal systematic troubleshooting will track down the culprit. Make one change at a time, so you know what each change does. Cubeowner forums are a good source of help. A search will turn up info on most any problem.

 

[BeniD82]

Hey There!

My Cube has the tendency to shut off if I move it around. I found out that in my case this is caused by USB connectors on the bottom of the cube. The connectors are in terrible shape (they look VERY ABUSED, bent/broken pins, warped houing - yeah, it's ugly) so when you move the cube, anything plugged into the connectors (especially the Cube-specific Harman Kardon speakers) will cause a short which will shutdown the cube if it's running, and also won't allow me to start it back up. Wiggling on the connector will usually fix it (may take a a few nudges but it will boot up again).

Like I said, as long as I won't touch/move/pull/tug on the plugged in USB devices she's purring like a kitten, but boy if you move her ... she definitively doesn't like to be moved } I'll have the conectors replaced by a professional sooner or later (my soldering skills aren't *that* great) because it's definitively a pain dealing with faulty USB connectors on the Cube, especially when considering that USB really is the *only* way of adding additional functionality to the system (other than FireWire, but honestly other than hard disks or camcorders/webcams I haven't seen FireWire being used for anything else).

If I were you I'd turn the Cube upside-down and inspect the USB connectors to see if there are any broken or bent pins. Specifically look for any pins touching the metal housing because like I said this will cause a short which will not allow the Cube to boot; it will appear as if your Cube had a bad PSU or bad logic board, no startup bong, video, etc. In my case, once I get my connectors fixed I'll just plug in a self-powered hub into the connectors so I won't have to worry about any more wear and tear on the box because USB is so heavily used on this machine.

Hope this helps!

~~ BeniD82