Previous 1 2 Next 16 Replies Latest reply: Jan 30, 2013 8:18 AM by bubbamj
bubbamj Level 1 Level 1 (10 points)

So I have this 2002 PowerMac G4 MDD dual 1.33GHz that refuses to boot sometimes, and I cannot figure out why!

 

I just replaced the power supply, though Im not 100% positive that this new one is in perfect condition. I have to check the volts later.

 

I currently have a 80GB drive with 10.5.8 in it and sometimes it boots, other times I get the screen with the apple logo on it, then black screen, then it does one of two things. It either repeats and goes to the logo then black screen, then logo then black screen forever, OR it goes from the apple logo to a black screen and stays black and I can hear it doing something inside. Apperantly the speaker is broke and when I plug in headphones I hear the startup chime over and over and over with about 6 seconds between them EVERY time. Why?

 

I have tried using a different GPU, no effect. Booting from 10.4 CD or DVD, or 10.5 DVD, no effect. Still Apple logo then black screen. I took out the battery and hit the little button on the motherboard when it was unplugged and that didnt help. I can feel the heatsink and its hardly even warm at all, so not overheating...

 

Does anyone have any solutions? Im about to pull my hair out! I'd love to get this back in everyday usable condition, not just "once in a while" working machine!

 

Thanks in advance guys! If you need any more info on this machine, Id be happy to provide it, along with pics~


Powermac G4 MDD Dual 1.0GHZ, Mac OS X (10.5.8), PowerMac G4 MDD Dual 1.33GHz
  • bubbamj Level 1 Level 1 (10 points)

    I just tested the PSU with the directions from here: http://www.jcsenterprises.com/Japamacs_Page/Blog/D275729F-09DA-4FBB-96B3-BEEEB2C 04619.html

     

    and its fine up until step 5, where my +3.3V shows as 3.3 and VERY VERY quickly drops down to around 0.7v. Then step 6 is for +5v, and my readings for that was +17v! I tested it multiple times with the same result. I even tried other red cables and they all were identical at 17v instead of 5v.

     

    Is this a SECOND bad PSU?

     

    Any reccomendations? Id rather get another OEM one, but they are soooo pricey! Are the ATX mods easy? I dont want to destroy my Mac case to do it...

     

    Also, is this the ONLY reason it has a boot loop? Seems odd to me....

  • japamac Level 7 Level 7 (24,390 points)

    +3.3V shows as 3.3 and VERY VERY quickly drops down to around 0.7v.

    Capacitor leakage? Voltage regulator compromised?

    Then step 6 is for +5v, and my readings for that was +17v!

    Complete loss of regulation? Not good.....

    Double checked the voltmeter setting for 12v? Properly zeroed? I trust that you did, but just checking...

    Is this a SECOND bad PSU?

    Not looking good....

    Also, is this the ONLY reason it has a boot loop? Seems odd to me....

    That part is hard to say. I'd be interested in what a Verbose mode boot shows.

    Are the ATX mods easy?

    The connector rewire is the hard part and you lose +25V, so no Firewire or ADC. One could run with an adapted ATX and the door open for testing, though.....

  • bubbamj Level 1 Level 1 (10 points)

    I'm quite new to volt meters, and can barely use mine... How do I check those settings or zero it? My model is Innova 3320

    https://www.google.com/url?sa=t&source=web&cd=3&ved=0CDwQFjAC&url=http%3A%2F%2Fw ww.walmart.com%2Fip%2FEquus-3320-Innova-Auto-Ranging-Digital-Multimeter%2F146446 66&ei=2FPsUJT1KaSt0AHr7oCYDw&usg=AFQjCNGNt6HmHukde-ddt-gP-9PauASiWg

     

    I'm using the 10 MegOhm input DCV setting for the voltage checks. Is that wrong?

  • japamac Level 7 Level 7 (24,390 points)

    Switched to DCV, either AUTO or 20V.

    The meter is auto zeroing, so no worries there.

     

    10 MegOhm input

    Ohm is for resistance measuring.

     

    AC/DC Voltage measurement

    To avoid possible electric shock, instrument or equipment damage, do not attempt to measure voltages above 600V AC/DC. This is the maximum voltage that this instrument is designed to measure. The "COM" terminal potential should not exceed 300V AC/DC measured to ground.

    1. Plug the black test lead into "COM" jack of the multimeter then plug the red test lead into the "V" jack.

    2. Set the multimeter's Function/Range Selector switch to the appropriate ACV or DCV position as desired .

    3. Place the red test lead onto the positive side of the item being tested and the black test lead onto the negative (across the source/load) side of the item. Be careful not to touch any energized conductors with any part of your body.

    4. Read the results on the display.

  • bubbamj Level 1 Level 1 (10 points)

    Does that mean I shouldn't use the "10 MegOhm input DCV" setting on the dial? Which do I use then? The only other DC ones as far as I can tell are "DC mA" and "DC10A" settings. The others are all AC, then there is battery load testing for 1.5v, 6v, 9v, and 12v...

     

    Sorry for the inconvenience!

  • japamac Level 7 Level 7 (24,390 points)

    I just looked at the user manual, enlarged the photo of a 3320 and could see the "10 Mega ohm input impedance" over the DCV. Yes, use that one. The impedance rating is for those who need to know (need to balance with output impedance), should not be of importance in the PSU test and only served to confuse me.

     

    Sorry. I still use an "antique" analog multimeter.....

     

    Given that, it would seem that you can trust the readings that the meter gave you.

  • bubbamj Level 1 Level 1 (10 points)

    On a side note, my MDD's power light will go on when I turn the machine on, but as soon as I release my finger it turns off. Is this a power supply issue as well?

     

    Also, trying to flash a 5.70 BIOS 7800 GS to Mac, and I cant seem to find the right version of nvflash. They all seem to just sit there and do nothing... Tried 5.13 and 5.127.

     

    "nvflash --check" produces:

    "NVIDIA Firmware Update Utility (Version 5.13)

    Adapter: BR02 (0F5h)             (10DE,00F5,FFFF,FFFF) B:01,AGP,D:00,F:00"

     

    Under that is a blinking "-" and I let it sit there for half an hour. Came back and it was still just sitting there blinking. The heck?

     

    Ive tried nvflash 5.127 too, and that one doesnt even do anything AT ALL besides flash the dash at me. Doesnt even say "NVIDIA Firmware Update Utility"

     

    What do I do? Thanks!

     

    Message was edited by: bubbamj

  • japamac Level 7 Level 7 (24,390 points)

    my MDD's power light will go on when I turn the machine on, but as soon as I release my finger it turns off. Is this a power supply issue as well?

    A commonly reported symptom of a failed PSU.

     

    Isn't the command a:\>nvflash --index=X -4 -5 -6 -j nvmac.rom accepted after the check?

    GeForce 5/6/7 How-To

     

    Maybe try this for Geforce 7xxx cards:

    http://downloads.guru3d.com/nvFlash-v5.63---NVIDIA-Firmware-Utility-download-186 2.html

  • bubbamj Level 1 Level 1 (10 points)

    I will try that version, thanks!

     

     

    japamac wrote:

    Isn't the command a:\>nvflash --index=X -4 -5 -6 -j nvmac.rom accepted after the check?

    It doesnt even go back to "A:\" when I do the check. It sits there blinking like its doing something, though I dont think it really is, therefor I cannot even RUN the command after that! D:

     

    Thanks for the quick reply by the way. Would love a faster way to communicate with you if possible...

  • bubbamj Level 1 Level 1 (10 points)

    Here is what happens with all of my attempts... It just sits there like this:

     

    IMG_0668.JPGIMG_0671.JPGIMG_0672.JPG

  • japamac Level 7 Level 7 (24,390 points)

    Does the card work in Windows?

  • bubbamj Level 1 Level 1 (10 points)

    No, it doesn't.

  • japamac Level 7 Level 7 (24,390 points)

    Dead card.

  • bubbamj Level 1 Level 1 (10 points)

    Shouldn't be. Worked fine a year ago and I had it stored in its own drawer inside a static bag. No visible signs of wear or anything. It was on a Mac ROM back then, but I wanted to flash it to the OCed ROM, as my card is the BFG OC version to begin with. If it was dead, why would it even show up on the nvflash at all?

Previous 1 2 Next