New to Mac having powermac G4 issue

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Hi, I'm semi new to Mac, my ex g/f had one and I've wanted one since. I found a powermac G4 dual 1.42ghz mdd for $45 and said what the heck. The guy who sold it said it worked a week ago and all of a sudden wouldn't power up. Light comes on then fades when I take my finger off. I've read numerous posts about this issue and I've replaced the pram battery and hit the reset switch (held in for 5 seconds). To no avail, so then I found the diagram of how to test the power supply (http://docs.info.apple.com/article.html?artnum=95064). Well, I got my volt meter out and did exactly as the diagram said. And on the # 11 and 22 pin I got an alternating reading between 26 and 27 volts. It says that if it doesn't show a reading of +28v to replace the psu. Now my question is, is that an exact reading of +28v or give or take some? If it is exact, does it sound like I for sure have a power supply issue?

By the way, I've looked the logic board and processors over and I have not seen any flash burns or anything of that nature. I opened up the power supply and also did not see anything out of the ordinary, other than all the white (I assume themal paste) just strewn randomly on the psu. Almost looks like someone went nuts with a caulk gun. The fuse was also in good condition.

Any help would be greatly appreciated as I am excited in getting my first Mac up and running, even though it is an older one. Thanks again.

Brandon
 
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Also a bad video card or the wrong video card will stop the machine from working. Try just one stick of memory.
 

pigoo3

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Light comes on then fades when I take my finger off.

This is REALLY a very vague statement...a subject in the sentence would help.

As far as your issue. You said that, "The guy who sold it said it worked a week ago..."

My questions to you are:

- How long have you had this computer?
- Did you buy it, and then it sat around for a while until you had time to play with it...or did you buy it, and started "messing" around with it right away?
- Did this computer work properly at all (at any point) as long as you have had it?
- Did it ever successfully "boot" up?
- If it did boot up ok...were you able to "play" around with it, and if so, for how long?

I'm trying to get a better idea of the situation.

Thanks,

- Nick
 
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I bought it 2 days ago. As far as, "it" lighting up, then fading, that would be the power button. No, it hasn't worked at all since I've had it. The person I bought it from stated in the add that it worked a week ago, which would be about two weeks from today, but then quit powering on. So I haven't been able to boot at all. I'm not too worried if I have to replace something like the psu because as I stated, I bought it for $45. But if I have to start putting a couple hundred dollars into it, then I will scrap it.

I'm actually thinking about taking it to my local mac repair store and just paying the $35 diagnostic fee. Then I can make the call of whether or not it is worth fixing. Thanks for your replies, and I will get back soon to let you know what I did with it.

Brandon
 

pigoo3

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I bought it 2 days ago. As far as, "it" lighting up, then fading, that would be the power button. No, it hasn't worked at all since I've had it. The person I bought it from stated in the add that it worked a week ago, which would be about two weeks from today, but then quit powering on. So I haven't been able to boot at all. I'm not too worried if I have to replace something like the psu because as I stated, I bought it for $45. But if I have to start putting a couple hundred dollars into it, then I will scrap it.

I'm actually thinking about taking it to my local mac repair store and just paying the $35 diagnostic fee. Then I can make the call of whether or not it is worth fixing. Thanks for your replies, and I will get back soon to let you know what I did with it.

Brandon

Thanks for the additional info.

Yes I figured that you meant the "Power Button"...but is really wasn't 100% clear...so it's best not to assume.

Good...you also cleared up that you knew before you purchased the computer that it did not turn or power on properly.

I'm assuming that when you say that the power button "fades" when you take your finger off...that the hard drive really doesn't spin up. Is this true?

It does kind of sound like the power supply may be bad. I used to have a 1.42ghz MDD...and had some problems with it...and I also thought I could have had a power supply issue...but it ended up not being the power supply...because my computer would boot up ok.

But...the power supplies for the G4 MDD computers can be pretty expensive. I remember them being around $125 bucks for a used one on e-Bay...and over $200+ for a new one.

Personally I wouldn't spend the $35 for the diagnostic check. You already spent $45 on the computer...so $35 more will just be throwing good money after bad. But the diagnostic would or should at least veriy that it's the power supply or not.

But if the diagnostic does verify that it's the power supply...then you will have to spend $125 to $200 for a replacement power supply. That would mean that you would be into this computer for $205 to $280 dollars ($45 + $35 + $125 to $200).

On the positive side...I think that you could sell this computer on e-Bay as a non-working computer (parts only)...and probably recover your $45 bucks + some extra...since these computers (even parts computers) still probably sell for $100-$150...maybe even more.

I sold my G4 1.42ghz MDD about a year ago for $250 on e-Bay...as a parts computer.

You could also mention that you think that the power supply is bad. But to some folks the computer case, motherboard, dual processors, and CD/DVD are worth money.

At least you knew when you bought it that the computer had problems...that's why you got it so cheap.

Maybe if you get some decent bucks from selling this computer on e-Bay...that the money may finance getting a better Macintosh computer that works...so you have a Mac to play with.

Hope this helps,

- Nick
 
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Thanks for the reply Nick. I'm thinking about going on ahead and taking it into the mac store to get it diagnosed. I don't mind spending the amount that I will be, I just don't want to over do it. I found a couple power supplies from between $110 and $145 with a $30 rebate for the old psu. Kind of like trading in your car alternator or starter. So if I get into roughly $200 I think it will be worth it. That is.....if it is the psu.

I'm using an older pc right now, with a P4 3.0ghz HT, 3GB of Ram and a 120gb hard drive. So older computers do not bother me. I am actually very satisfied with what I have, like I said, I just want to try out a mac. Maybe in the future I will purchase a new one. My pc is also agp video, which I upgraded recently to the Radeon HD3850. This card is a beast for what it is. Too bad I didn't realize I can't use it in the powermac, without flashing it. That is a little much for me.

But the budget that I am on, I don't want to spend more than $200ish. I am banking on the fact that the psu is bad, and if it is then I can stay in that ballpark. I've found used powermac G5's for roughly $400 but that is a little past my budget for the moment. That's why I want to try and stick with the G4. I'm going to contemplate it a little more and make my decision. You guys have been very helpful, and I appreciate it.

Brandon
 

pigoo3

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I found a couple power supplies from between $110 and $145 with a $30 rebate for the old psu. Kind of like trading in your car alternator or starter. So if I get into roughly $200 I think it will be worth it. That is.....if it is the psu.

But the budget that I am on, I don't want to spend more than $200ish. I am banking on the fact that the psu is bad, and if it is then I can stay in that ballpark.

Well if you don't mind spending up to a total of $200 on this computer...that's your call.

I don't want to be negative, but just keep in mind...there's always a chance that the power supply may not be the only problem. I'm not saying there will be additional problems...but since you can't boot the computer to the desktop...you will never know until you can boot the computer.

BTW...I was just checking e-Bay...and here's an auction for a dual 1.0 ghz processor MDD computer, with a Buy It Now price of $199.95 (plus shipping).

Apple PowerMac G4 1GHz DUAL MDD,1.5GB,80GB,DVD-RW - eBay (item 260465593702 end time Aug-27-09 11:43:34 PDT)

Yes this computer has a slower CPU than the MDD you have...but it WORKS!

Just some additional info for you before you spend an additional $180 bucks on this computer ($35 on a diagnostic test & $110-$145 on a used power supply)...without assurance that it will work.

And no...I'm not sure if you can use/swap the dual 1.42ghz CPU in your MDD and put it into the MDD computer on e-Bay.;D

Good luck with what you decide to do,

- Nick
 
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Did you disconnect the hard drive and pull all the memory except one stick and try to boot? Make shure the PS connector is seated. Try all theses little tricks before you spend more $.
 
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Just wanted to follow up. I went with my gut instinct and picked up a refurbished psu from a friend of my boss who works at a local repair shop. Paid $25 (and some barter work, as I am a painter) for it, and the G4 is up and running. I'm pretty happy that I made the choice. But it could have went either way. I didn't take it in to have it diagnosed so basically all I have in it is roughly $100 after the job I'm doing. I guess a $100 powermac G4 dual 1.42ghz (fw800) with the ati 9800pro and 2GB of ram isn't too shaby. Haven't messed with it too much yet. But I will spend this weekend playing around with it to see what I think.

Thanks again everyone for all your help.

Brandon
 
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Congrats on getting it working...always nice to keep the old stuff running!:)
 

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You got a great deal on that Power Supply. The PS for the Dual 1.42 MDD is quite expensive! Good going and glad to hear it was the issue and it now works.

Hope you enjoy your MDD. That was the one machine I wanted and at the time could not afford.
 

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