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#1 2007-11-02 10:42 pm
- PorkChop
- Member
- Registered: 2007-07-26
- Posts: 12
G4 Quicksilver won't boot
I have a 733 G4 QS, Radeon 9800 Pro, 1.5GB ram. I went to start it up and the drives and fans start to turn but then the whole machine shuts down after a second. I have tried zapping the PRAM, new PRAM battery, unpluging all devices, and still nothing. When I hit the power button the red LED on the logic board flashes for a split second but then turns off with everything else. Any suggestions?
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#2 2007-11-02 10:51 pm
Re: G4 Quicksilver won't boot
Two more things to test:
1) Bad RAM? Try removing the DIMMS and reinstall them one at a time to find ones that are bad.
2) Bad Power Supply? This is hard to test unless you happen to have another good one around.
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#3 2007-11-02 11:30 pm
- PorkChop
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- Registered: 2007-07-26
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Re: G4 Quicksilver won't boot
I tried removing the dimms one at a time but no luck. If the power supply was dead wouldn't the thing not even turn on for the split second?
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#4 2007-11-03 6:16 am
- Orion
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- From: America's Dairyland
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- Posts: 2900
Re: G4 Quicksilver won't boot
Try resetting the CUDA switch. Its a small round button on the motherboard. I can't remember exactly where it is (I think near the RAM slots) but if you press that button, it will reset the motherboard. Mine did a similar thing after I added RAM one time. Took care of the problem. Just push it once, count to ten and then try booting again.
The farmer is the only man in our economy who buys everything at retail, sells everything at wholesale, and pays the freight both ways. -John F. Kennedy
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#5 2007-11-03 6:42 am
Re: G4 Quicksilver won't boot
Also remove and reseat every card and connector you can find inside your Mac. Cards and connectors can become gradually unseated by vibrations and something like a not quite fully inserted video card can cause your symptoms.
If that fails try disconnecting your Hard drive, and see if it will boot to a question mark or not. A catastrophically failed HDD can sometimes do what you describe.
Basically if the above fails, you will want to remove things until you are down to the empty MoBo/cpu with one ram stick to eliminate possibilities. If you get everything off and it still won't even stay powered you have a power supply or MoBo issue in all likely hood.
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#6 2007-11-03 8:18 am
- PorkChop
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- Registered: 2007-07-26
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Re: G4 Quicksilver won't boot
I tried unplugging everything, and I've tried resetting the mother board several times. Still nothing. If I take it to the genius bar at my local apple store will they be able to tell me if its the power supply or the board?
Damn, first mac to ever die on me.
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#7 2007-11-03 8:57 am
- Nefarious
- Snow Meiser
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- Registered: 2002-09-30
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Re: G4 Quicksilver won't boot
Probably yes. $ 50 charge will apply. The inspection won't be free.
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#8 2007-11-03 9:14 am
- PorkChop
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Re: G4 Quicksilver won't boot
Do they have the parts available to fix it there? I'm sure a new logic board is $$$
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#9 2007-11-03 2:04 pm
Re: G4 Quicksilver won't boot
Did you add any new items (RAM, drives, cards, etc.) right before this happened? Or do any unusual traumatizing behavior - like moving, dropping, static electricity by touching internally parts without discharging first? Sometimes that's a giveaway to what can cause these problems.
Last edited by adamjg (2007-11-03 2:04 pm)
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#10 2007-11-03 2:19 pm
Re: G4 Quicksilver won't boot
http://resale.headgap.com/bobsmactips.html
If you want to dig deeper, this place has some relevant tech tips. It's a long page though. About 2/3s of the page down you'll find:
"Help! I pushed the CUDA Switch on my G3 or G4 and it still is not working
LET ME REPEAT: BEFORE YOU GET TO THIS POINT, you may want to ask yourself what happened just before the computer quit working. Perhaps taking out that new stick of ram or that new PCI card will get your system working before going to extreme measures. Even items that were working okay but recently installed may be suspect. Sometimes things fail. Try taking them out first.
Sometimes computers lose their mind. Don't ask me why or how it happens but it does. Sometimes you simply have to totally discharge the computer. One thing I have learned about the Blue and White G3 and G4 computers is that sometimes pushing the CUDA is not enough. If your machine still is dead, then try the following.
* Unplug the Unit
* Remove the Battery
* Push the CUDA Switch (count to 5 slow)
* Push the Start button on the front of the computer (count to 5 slow)
* Let the unit sit for 15-30 minutes
* Replace the Battery
* Plug it back in, and push the start button
Amazing! It works again!! If it doesn't I usually repeat the steps above, pull the ram, and let it sit overnight. Make sure you only have the keyboard, mouse and monitor plugged in. I usually also remove PCI cards and leave only one stick of ram. If it doesn't work after this it is take it to the shop time (or ship it to us)."
Last edited by adamjg (2007-11-03 2:22 pm)
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#11 2007-11-03 2:44 pm
- PorkChop
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- Registered: 2007-07-26
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Re: G4 Quicksilver won't boot
The day before I pushed down on the RAM sticks because I got the 2 beeps when I powered up. I ran a memory test and all checked up ok. I'll try to leave everything unplugged tonight. I think the logic board is bad, since now when I hit the power button the red LED on the board doesn't even flash anymore. Is Ebay the only place to buy a replacement board?
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#12 2007-11-03 3:00 pm
Re: G4 Quicksilver won't boot
Sounds like the logic board if you ask me, i had a sawtooth do the same thing once. I just got rid of it since they wanted an arm and a leg for the logic board
SlackWare Linux.
Because it just works.
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#13 2007-11-03 3:33 pm
- PorkChop
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- Registered: 2007-07-26
- Posts: 12
Re: G4 Quicksilver won't boot
Yeah, if I cant find a board for cheap I'll end up getting another G4 and just transfering the video card, drives and ram over to the new one. I'll end up parting out what ever is left and selling
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#14 2007-11-03 4:23 pm
Re: G4 Quicksilver won't boot
FYI, I've revived seeming dead computers (G3s) by unplugging all the major components (and batteries), letting sit for a day or more, pressing all the reset and CUDA buttons, and carefully putting all the stuff back in (and trying alternate RAM and Drives too).
Sometimes that works, sometimes not!
Last edited by adamjg (2007-11-03 4:27 pm)
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#15 2007-11-03 4:46 pm
- Orion
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- From: America's Dairyland
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- Posts: 2900
Re: G4 Quicksilver won't boot
I got a MDD G4 motherboard off ebay a year ago for about $125 and shipping. Getting it from an apple dealer would be really expensive, though getting it from ebay means used parts.
The farmer is the only man in our economy who buys everything at retail, sells everything at wholesale, and pays the freight both ways. -John F. Kennedy
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#16 2007-11-03 10:31 pm
- PorkChop
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Re: G4 Quicksilver won't boot
Just picked up a QS dual 800 for $137. So I'll be parting out the 733 and selling off the stuff that still works, along with the dual 800 CPU since I have a gigadesigns CPU upgrade on the way. Thanks for the help everyone.
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#17 2007-11-04 12:16 am
- pkmgarf
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- From: Sussex, WI
- Registered: 2007-06-13
- Posts: 459
Re: G4 Quicksilver won't boot
I was going to say, there are mobo's all over eBay. I got a Giga E board for $28 shipped. Anyway, good luck with the new endeavor.
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