G4 quicksilver wont power up.

So my G4 quicksilver decided it doesn't want to power up anymore. It turns on and the fans spin, but it has no display. I reset the pmu, checked all of the connections, and made sure the ram was installed correctly. Any suggestions as to what my next step is. Oh, The red light on the logic board does turn on and stays on.
Thanks in advance for any and all help given.

Does the power light come on at the front and then dim out?

It could be the battery on the motherbaord, like this
Sanyo CR14250SE 3V/ 850mAh Lithium 1/2"AA" Memory Backup : Computer Backup Power | RadioShack.com

Also try reseating the graphics card, and after that sounds like a fried logic board alas!

i already replaced the logic board. I forgot to mention that. Sorry. I'm thinking it's the processor. Anyone in agreement?

Replace the logic board yourself and if so was it the identical model? There are three or four, and maybe even more with DP models, different logic boards just in the Quicksilver model.

harryb2448 said:

Replace the logic board yourself and if so was it the identical model? There are three or four, and maybe even more with DP models, different logic boards just in the Quicksilver model.

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Yeah, It was the correct logic board. It appeared to work after replacing it but failed after about 2hrs. I'm guessing it wasn't the logic board in the first place. Since i am new to working on mac's i didn't reset the pmu on the first logic board which i believe would have given me the same result as replacing the board and resetting the pmu on the new board. I am going to put the original board back in and see if it will fire up, but i am really leaning towards it being a bad processor. I'm thinking it fails once it gets hot from the processor being under load from heavy usage.

Having added that have no doubt you are correct. If you go through auction sites you can get any amount of logic boards for the various models, but processors are like hens' teeth ~ very, very scarce. This leads one to believe more processors die that logic boards as the machine gets older.

It would be possible if the logic board checks out to use an updated CPU from OWC etc., but the coast is prohibitive. Much cheaper and easier to buy a later model sadly.

If theres something wrong with the Video card the machine will not boot.The best way to test is to unplug the Hard Drive and see if you get the Flashing ?

Mac SK said:

If theres something wrong with the Video card the machine will not boot.The best way to test is to unplug the Hard Drive and see if you get the Flashing ?

Click to expand...

unplugged the hard drive, but not sure what "flashing" im supposed to be looking for. Oh, it still does the same as before.

Flashing of the power on/off button.