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[supernova777]

ok ive jut been told a trick to check the powersupply
u can use a paperclip to connect the green + black section of the psu connectors to make contact and start the psu without it connected to the computer;
i will do this to see if the psu will start + stay on

[supernova777]

ok i have confirmed it with this trick!

THE POWER SUPPLY IS DEAD AS A DOOR NAIL!

connected greeen power on pin to a black ground. and...
exact same results! it tries to start and fails.

so theres a chance i didnt kill my mac after all!

my next question to investigate will be..
is the power supply repairable by an electrician?

[Protools5LEGuy]

ok i have confirmed it with this trick!

THE POWER SUPPLY IS DEAD AS A DOOR NAIL!

connected greeen power on pin to a black ground. and...
exact same results! it tries to start and fails.

so theres a chance i didnt kill my mac after all!

my next question to investigate will be..
is the power supply repairable by an electrician?

Where did you find the instructions for testing a Mac PSU? I know HOW only on PC-ATX.
For sure a good old skool tech can repair, but sometimes is cheaper to ebay another because of the time it takes to. In Spain a good tech can take 40-70 euros to repair (that old psu)
On the other side, a complete recap of the PSU with good quality condenser will make the computer more stable after 11-15 years of service.
The question is : Do you need ADC? You have an ADC monitor? If you use DVI or VGA and your card is "PC-born" you can use a PC ATX PSU with the adapter-cable from ATXG4PSU you mentioned before. I am not sure about Mac cards with ADC without the "only mac" +28 volts from original PSU but for sure Diehard or Japamacs should know it.
I think that the clever solution for a PowerPC user in this decade is to prepare themself for use PC-World ATX PSU from the B&W to the QS'02 (The PSU of the MDD is another beast of non-ISO dimensions). Motherboards last longer than PSU and CPU most of the time.

[supernova777]

i found a russian place that repairs... they said 50$ to fix.
but... i have no guarantee how long it will last..
but if i buy one from ebay etc the same thing could happen..
these are very old computers now.. some component in psu can easily die.
the best long term solution is to create an adapter to modify pin out  from this dead one..
using a atx power extension cable and cutting the connectors off of this dead psu
and fusing them with the extension to create an ATX-to-QS-Pinout PSU adapter cable
that way i can always just use a new ATX power supply
but the problem is that this will never provide the +25 volt for the firewire devices

and yes u are right most people will ask for 70-100$ to even look at repairing this
i have taken the psu out of the QS..
its a tuff decision, because i ahve another MDD dual 1ghz i can buy with keyboard + mouse
+ 2 new harddrives inside for 50$ so its almost like i have to turn my back on this old quicksilver..
which is sad;(

[supernova777]

http://www.instructables.com/id/Fix-a-dead-power-supply-using-a-Hair-Dryer-Reflow/

^^ this might actually work for me... im going to try it;)
i believe there has been some failure inside the psu transistor..
change in temperature might just allow it to start like it did for this man in his video

[supernova777]

yep no go on the hair dryer trick.. it probably needs some capacitors fixed inside.. i wonder if i could actually fix it by replacing the caps. maybe i will leave it unplugged for a few weeks to make sure its discharged and maybe one day i will get the courage to try and fix..

[Protools5LEGuy]

The hair dryer makes 3 things: Discharge condensor. Change relays state. Resolder.
If a relay or a fuse is involved it may works sometimes.
Make yourself a ATXG4 cable or order it! Buy a thermaltake and you are back to business!

[supernova777]

apparently the ATXG4 guy doesnt respond to emails..

http://www.jcsenterprises.com/Japamacs_Page/Blog/EA215F16-F592-4CF7-AA8A-496D5323F6BC.html

this is making the sawtooth look more + more desirable..
perhaps with a 1.0ghz + upgraded cpu..
because of the almost identical ATX psu pinout

very easy to mod a atx psu for a sawtooth..
not quite the same for a QS..

[supernova777]

in case the ATXG4 website goes down heres the pinouts for future generations;)

[supernova777]

http://www.applefritter.com/node/23857

this guy did a good job of fixing his mdd..
i could always do something like this but looks like alot of work;) heheeh

[Protools5LEGuy]

It is unknow if firewire works without the original PSU. Some says it needs +28 volts. If you still need firewire (and have a pci slot free) you can buy a texas instrument pci firewire interface on ebay. http://www.ebay.es/itm/3892D122-4-PORT-FIREWIRE-PCI-CARD-1394-PCI-/360829715364?pt=UK_Computing_ComputerComponents_InterfaceCards&hash=item54032083a4

Never buy a firewire card with via-chipset. Some agere should work, but for sure go on texas instrument chipset. You can't go wrong

[Graveyard]

The hair dryer makes 3 things: Discharge condensor. Change relays state. Resolder.
If a relay or a fuse is involved it may works sometimes.
Make yourself a ATXG4 cable or order it! Buy a thermaltake and you are back to business!

How the hell does a haidryer discharge a capacitor? In all my years working with electronics, i have never heard of something like this. Also, how does heat influence the tiny relays?
Relays are more heat resilient than you might think, and capacitors don't discharge into heated air unless there is 90%+ humidity. And not even then.
Resolder? Not a friggin' chance. It heats up the printed circuit board, and you may get a connection because of the heat induced dilation in a circuit that otherwise has desoldering points.
The hair dryer doesn't have enough heating power to resolder. My wife has a 1500W Zepter hair dryer. It burns like a mofo when close to the skin at maximum power. That bad boy is not even close to heating the solder to its melting temperature even when i keep it lose to the circuit for more than 5 minutes.

[DieHard]

Hey Graveyard... the whole hair dryer thing is some hilarious shit... I love it... I Remember using that trick to temporarily wake up dead cubes.. found it below, read these postings

http://www.cubeowner.com/forums/index.php?showtopic=13846

Of course, you are right, any real "re-flowing" or "re-balling" needs an expensive piece of precision soldering station (not a frickin hair dryer); I also remember rip-off guys on ebay charging $49 to $89 to "Fix" HP dv2000, dv6000, and dv9000 notebooks that had the faulty vNidia GPUs that would melt off the motherboard... they used a high heat hair dryer and some tinfoil... would fix the thing for about 3 weeks....lol.

Obviously, if a hair dryer fixes something it is temporary... and eventually a capacitor needs to be changed or a component replaced or professionally reflowed... read the cube thing... it is so funny, some people can get years out of the same power supply if they don't unplug it... go figure that one out 

Some guy said it even works on a G5, but I never tried that one... as far as I am concerned, G5s re all boat anchors, when they break it's scrap time... definitely the worst engineering to come out of Apple... high system failure rates on both liquid cooled and non-liquid cooled models.

[supernova777]

damn this stupid lil box:D

i think this might actually be rare but standard size psu used by other "BTO" or custom computers (like dell, hp etc)
i saw somewhere a link to one by "Delta Electronics" thta is same 344watts + pinout (22+4) perhaps i should contact the psu companies to see if somewhere someone still manufactures psu's of this nature.. i wouldnt mind buying a new psu if i knew it was NEW
and likely to last another 10 years!

[Protools5LEGuy]

You say its broken your PSU? Open it an see it!

[supernova777]

yes i have it open.. i cant see any caps that are burnt out but its quite crowded + obscured inside
im pretty sure it is broken tho..

it should stay running doing this green/black wire paperclip jumpstart trick.
i guess ill have to try another ACBEL psu and see what it does

[supernova777]

http://web.archive.org/web/20090104070804/http://homepage.mac.com/josephk/G4_mod.html

im gettin a crazy idea here boys + Girls...
should i take the 867mhz quicksilver cpu
and throw it in my g4 450mhz sawtooth?

this guy did it! hes got 2mb cache +



shame its osx 10.1 doesnt show the mhz etc

[supernova777]

Quicksilvers have a second +28V line on pin #9, this pin is not used
on Gig-E or DA G4s. Otherwise the PSUs are pretty much the same, 338 W
vs 344 W in the QS. If you have a Gig-E or Digital Audio PSU and you
want to use it in the Quicksilver you could split the +28V from pin
#22 and splice it into pin #9. The QS also has a 4-pin connector that
the DA doesn't so you might need to splice that piece from the old PSU.

http://osdir.com/ml/g3-5-list/2009-11/msg00625.html

so it seems its not so hard a task to get a DA/Gigabit PSU to power a QS

[supernova777]

peecee works for me i'm running a QS 733 overclocked to 933 with a pc ATX supply here. i used the +5vSB for pin 22, +12 for pin 9, changed pin 8 to +3.3, changed pin 19 to GND, and so far no problems. i used an ATX extender and modified the wires in the extender so that any standard ATX supply could be plugged in without worring about wires and such. watch out, on the seperate 4 pin +12v feed connector, it's backwards from the ATX supply (swap yellow and black) at the logic board end. compare with the original supply to double check!

i gather from reading boards that external power firewire devices would not work, and using an ADC monitor would not work. i have neither, so can't comment. i'm using a flashed 9800, 1.5gb ram, sata pci card, and a couple of 500gb drives, and have not had a single problem. best of luck.

http://forums.applecentral.com/ubbthreads.php/topics/475402/G4_to_ATX_conversion

seems like ill have to go ahead with this idea.. !

[supernova777]

well i just spent the last hour or so making sure i had the wires wired correctly....
and i did the modification in the same way that japamac did on his jcsentperprises site -- in that i used an atx extender -- cut off the last 2 pins to make it 22 pin instead of 24
pin so the male end would fit into the female connector on the QS mobo... other side just inserted 20pin into 24pin (from the atx -> adapter).. and then reversed the polarity on the pc 4pin double 12v+dbl ground.. connected it... and. after all that..

it does the exact same thing as it does with the QS power supply in it..
soooooooooo.. im not sure wtf is up.

whether its the PSU or the logic board.. or both..
the cpu is prob ok still..

man what a piss off!!!!!!!!!! 

total computer loss..
because i was up late messing around with a video card upgrade to a nonsupported card
something i didnt even neeed. the computer was working great...

sigh