iMAc G5 keeps shutting off

[thomgirl]

I have a refurbished iMac G5 that randomly just shuts off. It makes a little "zzzttt" sound, like something is short circuiting and then dies. Sometimes I can power it right back on and sometimes I have to unplug it and wait a few hours before it will come back on. While it's running, there are no issues. It functions beautifully. Anyone else had this type of problem or can you suggest a solution?
Here's the info on it:

Mac OSX 10.4.1,
Machine Name: iMac G5
Machine Model: PowerMac8,1
CPU Type: PowerPC G5 (3.0)
Number Of CPUs: 1
CPU Speed: 1.8 GHz
L2 Cache (per CPU): 512 KB
Memory: 1 GB
Bus Speed: 600 MHz
Boot ROM Version: 5.2.2f4


Thanks SOOO much for any advice anyone is willing to give! :0)

 

[Macky-Mac]

might be the start of the power supply failing

 

[thomgirl]

You may be right, since it makes that little "zzztt" noise sometimes when it's trying to start, but won't. Do you know any easy solutions to this prob, besides taking it to a repair place? I'm trying desperately to keep my costs down on this. Thanks!!!

 

[Macky-Mac]

unfortunately I think it's got to go to a repair place......and hope it's just the power supply!

a lot of G5 iMacs had this problem and sometimes changing out the power supply fixed it, sometimes tho it also meant changing out the logic board which def kicks up the price

 

[thomgirl]

Oh, geez. Well, thanks VERY much for the help! :0)

 

[orangejedi]

This same thing happened to my iMac G5: random shutting off.
As it turned out, the motherboard had gone bad, and it would be $700+ to replace it.
(Thank goodness for AppleCare.)
With a new motherboard, my mac works better and faster than ever (I'm typing this post on it.), but $700 is barely worth it for an old computer when you can get a new one for a little over $1100.
So if you have AppleCare (probably too late for a G5, though, I'm guessing), take it in - fast
Otherwise still take it in, but if the issue is the motherboard, then it may be time to look at a nice new aluminum intel.