Atx pg what is it

It's probably not a part of the spec that PSU manufacturers spend a lot of effort to get right. This power supply was installed in I believe, when the original Sparkle unit died. The computer seemingly has no problems other than one quirk. When you shut the system down properly Windows 10 and then you cut off the power, either with the PSU switch, the surge protector or pulling the plug, it will always turn back on immediately when power is returned. I've turned off everything related to system waking, return power states and anything else I found as a common cause of this problem.

I'm sort of hijacking my own thread, but I figure its worth asking whether the high PG delay might be related. Visual inspection inside the PSU shows the usual high build quality of Seasonic and no signs of heat or visible bad caps. Topic actions. First post, by Ozzuneoj Posted on , Ozzuneoj Offline User metadata Posts Joined , Location USA.

Rank Oldbie. Just want to quickly say thank you for all the very helpful replies. I've had to put the repair of these PSUs on my back-burner and will reply here again when I hopefully can grab a chance to get them back on the workbench.

I do still wonder if the ISENSE trimpot may have something to do with the sensitivity of the "Power Good" detection, but I will take the advice above not to touch it until I see how it's connected in the circuit, and have tested properly for ripple and any other reasons as to why the PSUs seem to be fully operational yet aren't giving out a PG signal.

In preparation I have constructed a capacitor discharger with LEDs based on this and this circuit so that I can discharge the big capacitors with a bit more visual assurance than just with the 2k ohm ceramic resistor I have used in the past.

Quote from: fudmuffin on August 17, , pm. I finally got around to dismantling and investigating these PSUs further and found that both units had a blown diode and resistor in exactly the same place, and sure enough this area is connected to the chip responsible for the "power good" signal, the PSH.

I tried replacing the burnt components on one board by canibilising the other but it doesn't seem to have helped, so perhaps the PSH chip has been damaged.

Here are photos of both relevant PCB's showing burnt components and also a pic of the reverse side showing the ICs. Out of interest, does anyone know what kind of diodes these would be? I can't see any markings I'd love ideas about what I could have done next, but but I think I'm out of luck on this repair and will move on to the next one As you can see from the pictures there is a "missing" diode HD4 next to the one that has overheated HD1 and I couldn't help wonder if it would helped to add a diode there The fact that both PSUs have failed in this same way makes me think perhaps there was a fault in the original design.

Well 2 cents of opinion I deal with PSUs a long time Power supply not only produces the necessary sites for computer power, but suspends the operation of the system until long as the magnitude of this voltage reaches a value that is sufficient for normal operation.

Each power supply before getting permission to run the system, the internal inspection and testing of the output voltage. If this signal is not received, the computer will not work. The mains voltage may be too high or low for normal operation the power supply, and it may overheat. Such a radical method of protection was provided by IBM, based on the consideration that in case of overload or overheating of the power supply output voltage to be go beyond the acceptable limits and work on that computer would be impossible.

He served on chip clock generator. The power supply diagnostics continuously monitors its outputs and stability of the supply, in case a fault or unstable voltages due to brownouts, deteriorated components, or input supply issues, the power good signal is withdrawn. This causes the timer chip to reset the processor continuously and thereby turn off the computer operations. Once the power supply resumes its normal and stable output voltages, the power good signal is again regenerated and sent to the timer chip to restart the computer operation.

Once a bad power situation detected, the computer is permanently reset and stopped quickly to avoid malfunction such as parity errors and malfunction.