Bringing a G4 Cube back to life

[smnbldwn]

In October, I was lucky enough to be asked to "dispose" of a PowerMac G4 Cube. It was complete but very dirty having being left in an outdoor shed for 11 years! I brought it home and gave it a clean, connected it, crossed my fingers and plugged it in. The fuse immediately blew in the plug and from researching the problem, it looked like the psu had died. As I couldn't get into the PSU and was quoted a lot of money to fix it, I bought an LED power supply rated at 28V, 250W and tried that. This time the computer booted up and ran. It worked fine for a few days except that there was a CD stuck in the drive. The CD was read by the computer and iTunes ripped it without an issue but it would not eject.

After a few days of normal use, I plugged in the PSU and heard a sparky sound and there was an "electrical" smell. Since then, the cube has been unresponsive. I checked the PSU with a multimeter and it is still producing 28.0V.

Could anyone offer any next steps in fault finding? I managed to use this machine to get hooked. It is very pretty and has pride of place on my desk. The keyboard and mouse were nice to use and it was usable on Mac OS 10.3.9. The last time it was started previously was 2007! I love macs and already have a 2005 PowerBook and a 2008 MacBook Air (both in regular use)

 

[EvilCapitalist]

I'd say your first check would be the VRM.  I'm betting with the machine living outdoors for 11 years that probably wasn't in the best shape to begin with and just finally gave up the ghost after being powered on again.

 

[Bolle]

And a dying VRM usually takes the logicboard and CPU board with it.

I have fixed dead VRMs and CPU daughterboards but could not yet get a logicboard to work again after it was stricken down by a VRM.

 

[Paralel]

In October, I was lucky enough to be asked to "dispose" of a PowerMac G4 Cube. It was complete but very dirty having being left in an outdoor shed for 11 years! I brought it home and gave it a clean, connected it, crossed my fingers and plugged it in. The fuse immediately blew in the plug and from researching the problem, it looked like the psu had died. As I couldn't get into the PSU and was quoted a lot of money to fix it, I bought an LED power supply rated at 28V, 250W and tried that. This time the computer booted up and ran. It worked fine for a few days except that there was a CD stuck in the drive. The CD was read by the computer and iTunes ripped it without an issue but it would not eject.

After a few days of normal use, I plugged in the PSU and heard a sparky sound and there was an "electrical" smell. Since then, the cube has been unresponsive. I checked the PSU with a multimeter and it is still producing 28.0V.

Could anyone offer any next steps in fault finding? I managed to use this machine to get hooked. It is very pretty and has pride of place on my desk. The keyboard and mouse were nice to use and it was usable on Mac OS 10.3.9. The last time it was started previously was 2007! I love macs and already have a 2005 PowerBook and a 2008 MacBook Air (both in regular use)

Blew in the plug? I take it you are not in the US, correct?

And a dying VRM usually takes the logicboard and CPU board with it.

I have fixed dead VRMs and CPU daughterboards but could not yet get a logicboard to work again after it was stricken down by a VRM.

I'm not too surprised, a VRM goes rogue, all hell really does break loose. If I had to pick one part not to go to s***, it would be the VRM. It's job is just too damn important.

 

[smnbldwn]

Correct, UK plugs still have fuses in them. In this case a 5A one.

 

[LaPorta]

I always wondered why the UK plugs were so flippin' huge, and then I learned about the fuse business.

 

[Paralel]

Correct, UK plugs still have fuses in them. In this case a 5A one.

Cool, that's what I thought. Used to live in the UK. Had to keep a box of fuses on hand, just in case I had a plug go stupid.

It's always better if you tell us you are somewhere that is 220 vs. the 110 in the US, which is assumed to be the default by most, because every so often, there actually are differences in the internal anatomy of technology by virtue of the fact that they are indeed 220, and if someone doesn't know that, you might get bad info unintentionally.

 

[smnbldwn]

Apple are normally really good at adapting from one voltage to the other, thankfully!

 

[olePigeon]

You can get GFCI cords in the U.S. too, but from what I've seen they're even bigger than the U.K. cables.

 

[Paralel]

You can get GFCI cords in the U.S. too, but from what I've seen they're even bigger than the U.K. cables.

Yep, and they're incompatible with certain types of breakers

 

[olePigeon]

I have an old string of Christmas lights from the 1960s.  2 prongs (not even polarized.)  It looks normal, except it has a tiny fuse build into the plug.  Fuse is still good.

 

[CC_333]

If you need, I have an extra VRM, CPU card and logic board. They work, as far as I know.

They're small and light, so shipping to the UK shouldn't be horrible.

PM me if interested.

c

 

[DomA]

I've got a entirely disassembled Cube. It was my first ever Mac and I couldn't bring myself to bin it. I tore the whole thing down and the parts have been sitting in a box (indoors) for years, presumably they still work. 

It's got the rarer 500Mhz CPU and an BIOS flashed nVidia 6200 (I think...?)

I'm in the UK if you'd like anything.

 

[Mikeyy00]

I've got a entirely disassembled Cube. It was my first ever Mac and I couldn't bring myself to bin it. I tore the whole thing down and the parts have been sitting in a box (indoors) for years, presumably they still work. 

It's got the rarer 500Mhz CPU and an BIOS flashed nVidia 6200 (I think...?)

I'm in the UK if you'd like anything.

How much for that CPU?

 

[DomA]

How much for that CPU?

£30 plus postage? I can't really test it without reassembling the whole computer though...

 

[smnbldwn]

I still haven't got around to investigating what is wrong here... I have just bought a multimeter so fingers crossed its a fuse, clock battery ,trip switch or something cheap... I got hooked in those three days it worked. Not bad on OSX Panther, not that much slower than my eMac 1.25GHz...