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b33faroni · Feb 3, 2006, 04:43 PM

My school just received a Powermac G4 donation from someone and since mostly everyone in my school barely knows PCs and XP let alone a Mac as it is, they gave it to me to fix up, for the person said there was something wrong with the hard drive. Well I open up the tower and its pretty dusty, but nothing that I havnt seen with other computers before. So I plug everything in and boot it up. The screen just comes up blank and nothing else. As I stare at it and try to boot it again I notice a strange smell coming from the computer. So I open it up and sure enough the computer smells like its burning (smells just like those popper things that kids throw that spark). Needless to say I turned it right off and let it be for a little. On monday Im going to try to just replace the hdd and narrow it down to what could be wrong with it. Had anyone ever had this happen to them, if so what was the problem? Just thought id ask to see if anyone else has or if this person just really screwed their computer up (which it may be cause the one USB port is missing the plastic insert inside and is bent to all hell). Thanks guys

Bill

b33faroni · Feb 6, 2006, 12:45 PM

Got more info, maybe you guys can help now. When I first turn the g4 on it stays on for about 30 seconds and then turns off. When I turn it on again it stays on. I get the smell that I described before, and it seems to come from in around the AGP slot area ish. Its not the video card itself because I switched it with another and that one worked in another computer. I tried to install a PCI Video card instead and got the same result. From there I went and switched HDDs, and go figure, that was not it either. So im guessing that it is the motherboard...which sucks cause dont happen to have any of them laying around heh. Any other suggestions before we scrap it? Thanks

jamil5454 · Feb 6, 2006, 12:47 PM

It might be the PSU.

b33faroni · Feb 7, 2006, 12:34 PM

Ok well I checked the CPU and it was perfect so i thought just for the hell of it to switch the logic board battery and that was it. I dont know why the battery smelled like it was burning, but o well thats fixed. So I was all happy and booted it up and bam, another problem...but this SHOULD be the last one. One of the built in USB ports are bent and the white insert is missing so I knew that one woudlnt work, but either does the other one..thats seems to be in good condition. I can still understand that so I plug it into an apple monitor and try to use the USB ports from the monitor, and that doesnt work either....which doesnt make any sense to me. So now I get the whole computer to boot up but cant use a mouse or keyboard. Its not the monitor because it works fine with another G4 powermac. Im thinking its the OS now and might reformat it. But first does anyone have any last suggestions and if I bought a PCI USB card are they universal or do I have to buy a specific one for macs? Thanks

SSharon · Feb 7, 2006, 02:03 PM

check the peripherals forum for recommendations on the usb pci card since it should say mac os x support. I have one in my g4 but I can't remember the brand off the top of my head.

b33faroni · 06:03 PM

Any other suggestions before I go spend like 20 bucks on a PCI card...id say maybe reformat the drive but sorta hard without a mouse or keyboard heh. I just find it odd that the monitor's usb ports didnt work but worked on another computer, I might hook up another hdd with os X on it to the G4 to see if its the OS or not

new newton · Feb 7, 2006, 06:53 PM

It's pretty doubtful that a battery would cause a burning smell when the machine is powered on. For one thing, the battery is always "on". Another is that they battery never takes a charge. It's basically a watch battery.

What you have there is a fire hazard, most likely stemming from a power supply problem. When people say "there's a problem with the hard drive" they're often meaning to say "there's a problem with the computer." To the layman, the tower is the hard drive.

You'd be negligent if you leave this machine plugged in when not in use. I never accept donations at my school, simply because people see the schools as a dumping ground for old junk.

b33faroni · Feb 8, 2006, 04:58 PM

New Newton, thanks for the advice, I never even thought of it that way... What im going to do it switch the Power Supply (I notice their different from PC ones so ill swap it out of another Mac) and let it run in my basement (concrete) just to make sure that its all good and no smell comes back. I just noticed the PSU sparks when I connect the power cord so I dont see that as a good sign either. However I still have the USB problem, it wasnt the OS or hdd, so I have no clue what problem it is. No USB ports work on it, whether it be the one damaged one on the tower, the good one on the tower, or ones in monitors. I am going to pick up a cheap PCI card from comp usa or somewhere just to see if thats the problem and just return it if not. If that doesnt fix the problem and noone else has any suggestions ill just scrap the beast for parts or something of the sort. Thanks guys, ne other suggestions are helpful

tooki · Feb 8, 2006, 05:45 PM

It's perfectly normal for a small spark to appear when connecting a live power cord.

tooki

b33faroni · Feb 9, 2006, 08:27 PM

Ok well I got a PCI USB card and everything is working flawlessly, well except the fact that I dont know the previous users Admin password (how would I go about upgrading or would I have to reformat it?) and that when I put in the airport card it does not boot up. I could live without the airport card, but it would be nice to have. Thanks for all your help guys, and if you know anything about that too.

gto47 · Feb 14, 2006, 02:06 PM

You can change the password by booting from cd. It's in the menu bar somewhere. I have a theory about your little situation. I've seen this a lot on old imacs because they actually only have one usb bus thats divided between two ports. This should not be the case on a power mac but its good for you to know just in case. I suspect that the power pins on the USB jack are indeed shorted together, closing the circuit when there is no load which is somehow preventing the other usb port from working. There is a trick that i once used on an old powermac 8100. It had two ethernet jacks, one AUII and one standard 10 base. The 10 base connecctor was damaged and causing the AUII jack not to work. Those of us who remember that lame standard will recall all of the apple ethernet to 10 base adapters that everyone used, and I had one. What i did was i amputate the jack from the board (very carefully of course) and sure enough the other ethernet jack worked. I would probably remove the USB port, or if you can just disconnect the portion that is not working although this will be difficult. I suggest doing this anyway because the short may be whats causing the burning smell. On pcs often if there is some sort of short on the motherboard the power supply will produce a burning smell. If this thing is going to be used in a school, i think you'd be a lot safer removing the dead usb ports.

b33faroni · Feb 14, 2006, 11:46 PM

Thanks for the advice man, appreciate it, ill look into it