Revenge From Mars
Bally, 1999Hey gang. I replaced my original AT PSU with an ATX using this guide:
http://antelopearcade.com/forum/posts/t4-Pinball-2000-AT-to-ATX-Power-Supply-Replacement
Now, when I press the power button, the PS and CPU fans come on for just a moment and go off. You can also see a light come on and go out on the prism board.
Any ideas what I messed up? The playfield is currently out of the game, but not sure if that matters.
Thanks, in advance.
The problem is probably that green wire that tells the power supply to come on. It looked like he had a couple of different ways of connecting it. You can try grounding it to the metal of the power supply if you don't have it that way now.
Quoted from Karetaker:The problem is probably that green wire that tells the power supply to come on. It looked like he had a couple of different ways of connecting it. You can try grounding it to the metal of the power supply if you don't have it that way now.
It is grounded by the switch, but I will try a direct grounding tonight. It's pretty small gauge wire. I could've made a not so great crimp on the QD. I would think that would cause nothing, but I'll give it a shot.
As stated, the green wire needs to be grounded.
If there's a switch on the power supply, make sure it's set to the correct voltage (110/220).
It is also possible your power supply doesn't turn on because the load isn't big enough (unlikely but possible)
Unplug the atx connector and just short the green wire to ground, does the fan start and stay on? If it does but doesn't turn on with the atx connector plugged in, there possibly is a short on the board and the power supply shuts down to protect itself.
Quoted from RC_like_the_cola:when I press the power button, the PS and CPU fans come on for just a moment and go off. You can also see a light come on and go out on the prism board.
The computer power switch should be a momentary-to-ground. That tells the power supply to turn on. If it stays grounded, after four seconds the power supply will turn off again.
Computers sometimes act this way if they don’t have memory or video cards installed. You might try reseating components and double checking any cables you might have unplugged.
Also verify the 20 pin connector is seated all the way.
Quoted from YeOldPinPlayer:The computer power switch should be a momentary-to-ground. That tells the power supply to turn on. If it stays grounded, after four seconds the power supply will turn off again.
Computers sometimes act this way if they don’t have memory or video cards installed. You might try reseating components and double checking any cables you might have unplugged.
Also verify the 20 pin connector is seated all the way.
I'll check more stuff tonight. I can say the switch is not momentary for sure. It took some wiggling, but the ATX connector is surely seated all the way. I'll try the reseating cards as well.
Thanks
Quoted from YeOldPinPlayer:The computer power switch should be a momentary-to-ground. That tells the power supply to turn on. If it stays grounded, after four seconds the power supply will turn off again.
Computers sometimes act this way if they don’t have memory or video cards installed. You might try reseating components and double checking any cables you might have unplugged.
Also verify the 20 pin connector is seated all the way.
What you are talking about is actually a behavior of a typical PC motherboard. The actual power supply doesn't monitor the power button directly. For the power supply to be turned on , that pin must be driven low. The circuitry that handles this on a PC motherboard can have many sources trigger that pin to low, be it Wake On Lan , Power up after AC power loss , Specific time and date, Power button, etc. When the PSU is used in the way OP is using it , the only signal it needs is that pin to be grounded. The second you remove it from ground , PSU turns off, otherwise it would be forever on...
I just noticed you said the playfield is off. Are you sure nothing is shorted anywhere ? Did you have any issues at all before removing the playfield and changing the PSU, or did you just want to update the PSU in there ? I don't know your particular machine , but if you are turning on the machine by shorting the green wire, the playfield shouldn't matter (unless some disconnected wire is pinched somewhere).
I would:
-Disconnect the ATX connector from the board
-Short the green wire to any black ground wire in the harness ( you can do this with a paper clip or long nosed pliers without cutting the green wire at all when you test)
If the fan stays on then , the PSU is working fine.
If it turns on and quickly off it could be the 110/220 switch or maybe even it could be a 220v PSU with no switch and you are trying to power it with 110,
Or that it requires a certain power to be drawn from one of the wires in order to actually turn on (a load) and this should be written on the label of the PSU,
That the power supply smart enough to not turn on the fan at all because so little current is drawn and there is almost no heat to remove. If you are using a 500-600W PSU and from what I quickly gathered this machine runs at about 200w max , then its very possible the PSU just doesn't need to run that fan.
Or that the PSU is simply dead.
If it doesn't turn on when the ATX connector is connected , but it did when it wasn't then it means a protection in the PSU is kicking it and preventing the psu to turn on and damage something. This is very typical of a short circuit protection and most decent power supply have that nowadays. It might even take a few minutes to be able to turn the PSU on after such protection kicked in.
Can you post a picture of the PSU label ?
Quoted from Roamin:I just noticed you said the playfield is off. Are you sure nothing is shorted anywhere ? Did you have any issues at all before removing the playfield and changing the PSU, or did you just want to update the PSU in there ? I don't know your particular machine , but if you are turning on the machine by shorting the green wire, the playfield shouldn't matter (unless some disconnected wire is pinched somewhere).
I would:
-Disconnect the ATX connector from the board
-Short the green wire to any black ground wire in the harness ( you can do this with a paper clip or long nosed pliers without cutting the green wire at all when you test)
If the fan stays on then , the PSU is working fine.
If it turns on and quickly off it could be the 110/220 switch or maybe even it could be a 220v PSU with no switch and you are trying to power it with 110,
Or that it requires a certain power to be drawn from one of the wires in order to actually turn on (a load) and this should be written on the label of the PSU,
That the power supply smart enough to not turn on the fan at all because so little current is drawn and there is almost no heat to remove. If you are using a 500-600W PSU and from what I quickly gathered this machine runs at about 200w max , then its very possible the PSU just doesn't need to run that fan.
Or that the PSU is simply dead.
If it doesn't turn on when the ATX connector is connected , but it did when it wasn't then it means a protection in the PSU is kicking it and preventing the psu to turn on and damage something. This is very typical of a short circuit protection and most decent power supply have that nowadays. It might even take a few minutes to be able to turn the PSU on after such protection kicked in.
Can you post a picture of the PSU label ?
I bought a case of these power supplies years back. They are 250 watt ATX and all of them have worked right out of the box. I can post a label this evening. Everything was fine with the game, I just read that replacing the PS and CPU fans were a must do preventative measure. I'm waiting on my Cliffy's to arrive, that is why I figured I'd go ahead and do the preventative PS replacement. The green wire has been cut per the link I posted in the beginning. I will first, try the recommendation of simply eliminating the power switch and grounding the pin to the metal case and go from there. I mentioned the playfield not being in the game because I'm not sure if it needs to be connected for the PC to boot since this is my first pin2K game.
Quoted from RC_like_the_cola:I bought a case of these power supplies years back. They are 250 watt ATX and all of them have worked right out of the box. I can post a label this evening. Everything was fine with the game, I just read that replacing the PS and CPU fans were a must do preventative measure. I'm waiting on my Cliffy's to arrive, that is why I figured I'd go ahead and do the preventative PS replacement. The green wire has been cut per the link I posted in the beginning. I will first, try the recommendation of simply eliminating the power switch and grounding the pin to the metal case and go from there. I mentioned the playfield not being in the game because I'm not sure if it needs to be connected for the PC to boot since this is my first pin2K game.
"Grounding pin to the metal case" Are you even certain that there is a physical connection between one of the black wires of the power supply , and that metal case? I suggesting doing the test with one of the black wires instead of the case.
Quoted from Roamin:"Grounding pin to the metal case" Are you even certain that there is a physical connection between one of the black wires of the power supply , and that metal case? I suggesting doing the test with one of the black wires instead of the case.
That's just what the guide said to do if you choose not to use the original power switch. Did you check the guide in the link in the original post?
I did check the guide, but you shouldn't use the chassis to ground the green wire. It can work if the chassis is properly grounded but the right way is to take any black wire from the psu, even one that is for peripherals where you have 5/12v and 2 grounds on a molex connector.
Quoted from Roamin:I did check the guide, but you shouldn't use the chassis to ground the green wire. It can work if the chassis is properly grounded but the right way is to take any black wire from the psu, even one that is for peripherals where you have 5/12v and 2 grounds on a molex connector.
Gotcha. I've done that mod on several of these power supplies for other uses, but was just following the guide since that guy was able to swap it out painlessly using that method.
Quoted from RC_like_the_cola:It is grounded by the switch, but I will try a direct grounding tonight. It's pretty small gauge wire. I could've made a not so great crimp on the QD. I would think that would cause nothing, but I'll give it a shot.
If that works like that for you then you can do as Roamin suggested and hook it to one of the black wires.
Direct grounding of the green wire to a black produces the same thing. Feeling defeated tonight. Will get back at it tomorrow.
Forgot to test with the ATX removed. Did this and get the same result. It powers for a second and dies. Maybe it's a dud out of the case. Will put in a different one and see.
Quoted from RC_like_the_cola:I can say the switch is not momentary for sure.
The switch MUST be momentary the way I understand it or the PC motherboard will power up and then power down straight away?
I could be wrong but you need to check if this is the case or not.
Quoted from RC_like_the_cola:Forgot to test with the ATX removed. Did this and get the same result. It powers for a second and dies. Maybe it's a dud out of the case. Will put in a different one and see.
With the Atx connector off if it doesn't stay on there is an issue with the power supply.
Quoted from pins4u:The switch MUST be momentary the way I understand it or the PC motherboard will power up and then power down straight away?
I could be wrong but you need to check if this is the case or not.
But this is not a PC! It is only the power supply, and as I have said earlier, the 4 second logic to turn off the psu is not implemented in the psu itself, but that is a function of a PC motherboard, not the power supply. I have quite a few ATX power supplies running, either in my arcade or my dozen mining rigs I have.. No matter what others keep saying, the green wire, signal named "PS_ON#", needs to be grounded to DC ground for the entire time you have the psu on. A motherboard will do just that, you press the button once, it pulls that pin low until you send a shutdown command, or if you hold the power button 4 seconds it will then pull the pin back high and the psu will turn off. When the pc receives a wake on lan event, it will also pull that pin low to turn on the power supply. There is a purple wire, 5v standby, that is always active when the psu is plugged. This 5v powers the power on logic, including wake on lan, the real time clock of the pc and the actual power button logic.
As you can see on this picture, I'm using this old Atx supply has a tester for some arcade boards I was repairing. All it requires is for me to jam those tweezers between green and black, leave them in until I want to turn off the psu.
20210609_062839.jpgQuoted from RC_like_the_cola:Forgot to test with the ATX removed. Did this and get the same result. It powers for a second and dies. Maybe it's a dud out of the case. Will put in a different one and see.
If you are connecting the green wire to a black wire then it should come on. I have some single strand wire for this and it works well for testing. I've used solder in a pinch. Roamin asked about a voltage switch 110/220 did you check and make sure it is on 110? I've seen power supply act like yours that had bad caps. But, if this is new it may be a "dud"... trying a different supply is a good idea.
Quoted from Karetaker:If you are connecting the green wire to a black wire then it should come on. I have some single strand wire for this and it works well for testing. I've used solder in a pinch. Roamin asked about a voltage switch 110/220 did you check and make sure it is on 110? I've seen power supply act like yours that had bad caps. But, if this is new it may be a "dud"... trying a different supply is a good idea.
Yes, the switch is set to the 115 mode. I'll try another supply tonight. At the very least, I'll test another out of my case and make sure grounding the PS ON line keeps it running as it should. I can always go back to the original AT PS that was working fine, but I was hoping to put a new one in for longevity.
Good news. 2nd PS out of the case works. It powers on and the prism card light stays on as does the CPU fan, etc. Still nothing on the monitor. I'm guessing/hoping that is because the playfield is not connected. Not sure. All connectors are connected as the were prior.
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