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NormPhillips · Jul 27, 2006, 02:30 PM

Hi everyone,

My Power Mac G4 450/DP is dead. It won't even turn on, AT ALL. I've tried restarting the PRAM, etc. Nothing's worked. No light, no hard disk spining, no fans turning on, nothing. Has my power supply failed? Or has my motherboard burned out? Is there anything I can do?

I just bought a new MacBook Pro 2.16GHz 15.4", but I was hoping to sell the old computer still. Is it even worth salvaging? If not, what's the cheapest way to get rid of it?

Thanks.

GORDYmac · Jul 27, 2006, 02:41 PM

Well, repairing the computer may offset what you would make from selling it. It could be a simple fix (power cord, power supply) or expensive (all that other stuff). Don't know 'til you go, you know?

The cheapest way to get rid of it is to trash it, but, that wouldn't be the eco-friendliest way. The AppleStore will take it off your hands.

Waragainstsleep · Jul 27, 2006, 06:12 PM

Does the red LED on the board flash when you try to switch on? Have you reset the board? (There is a button on it). If its completely dead, then you could look for a cheap PSU on eBay. Or get on Google and modify a PC ATX PSU to run it.

NormPhillips · Jul 31, 2006, 09:04 PM

I had a friend come over with another power cable. The computer still did not work. However, I was able to recover data off of the hard drive. It's most likely the power supply. Is it worth it to buy a new power supply and pay to have it installed in order to later sell the computer? How much will it cost?

BTW: NO LED flashes on the motherboard and I have tried resetting the board.

imitchellg5 · Jul 31, 2006, 09:43 PM

You could always take it in to a repair shop and they could tell you what is wrong. You could sell it, but you won't get much money for it. Or you could give it to someone that wants to repair it. If you want to get rid of it let me know

NormPhillips · Aug 2, 2006, 06:37 PM

I saw on eBay a 450DP G4 was just sold for over $300, and it has half the RAM, the oriiginal graphics card (a Rage 128 16MB, mine has a 128MB RADEON 8500.) However, mine is not in as good of a shape. How much would it cost for a new power supply and the service required to install that power supply?

DrBoar · Aug 9, 2006, 02:34 AM

Have you replaced the PRAM battery? A dead battery makes many macs to appear to be dead as a door nail.

Take a look at xlr8yourmac.com about using PC ATX powersupplies for the mac. You will not get 28V for a ADC monitor and you need to do some rewiring.

An option is to buy a bare G4/400 or G4/350 as cheap as you can and then use that PS in your computer. If you do the revese and move your CPUs to the other computer make sure that the new motherboard support dual CPUs. (also described at xlr8yourmac)

NormPhillips · Aug 9, 2006, 02:51 AM

Originally Posted by DrBoar

Have you replaced the PRAM battery? A dead battery makes many macs to appear to be dead as a door nail.

Take a look at xlr8yourmac.com about using PC ATX powersupplies for the mac. You will not get 28V for a ADC monitor and you need to do some rewiring.

An option is to buy a bare G4/400 or G4/350 as cheap as you can and then use that PS in your computer. If you do the revese and move your CPUs to the other computer make sure that the new motherboard support dual CPUs. (also described at xlr8yourmac)

Wouldn't an old PRAM battery just simply reset the time back to the mid 20th century? I believe years back I had to replace the PRAM battery because of the time constantly being reset. However, it's worth a try. Where can I buy a PRAM battery?

The others are helpful ideas though. Thank you.

Back up 15 and punt · Aug 10, 2006, 10:53 AM

About nine months ago my 450DP did the same thing. Apple charged me $250 to replace the power supply. No it works great. However, it might take them up to three weeks to fix it. It all depends on how hard it will be for them to get their hands are the part.

spork · Aug 10, 2006, 11:51 AM

My Ge DP 500 had similar problems as yours and it turned out to be a dead motherboard and it fried the video card when it went out.
Power supplys on ebay are around 100 bucks and installing requires allen key, screwdriver and maybe half an hour. It could also be the logic board, about the same price and harder to install, although also completely doable. Ideal would be test battery, then power supply, then think of mother board. You can use a power supply from either a Gigabit Ethernet or a Digital Audio to test if that is the problem.
I have an early G4 PowerMac PDF file which is great and has a troubleshooting section. Contact for it. Should be fixable so don't give up.