Page 1 of 1

Replacement ATX PSU

PostPosted: Wed Feb 26, 2020 11:16 am
by Carlo
Dear All,

I would like to change my ATX PSU of the d8b's remote computer. The link i've got from the d8b knowledge base is the following:

https://www.atxpowersupplies.com/250-wa ... I-240G.php

Is this a direct replacement of the ATX psu please?

Does this replacement ATX PSU got all the wires needed to supply the other boards in the remote unit including the motherboard?


regards

Carlo

Re: Replacement ATX PSU

PostPosted: Fri Feb 28, 2020 1:33 am
by arjepsen
If you have the new motherboard, I *think* you can use any old atx supply .
However be aware that an atx psu is turned on differntly that the old one!
For turning on an atx psu, you have to short two pins on the motherboard.
Some people (me included) short two of the pins on the atx connector - this means it turns on everytime it gets mains power - similar to how the old one worked.

Re: Replacement ATX PSU

PostPosted: Fri Feb 28, 2020 10:15 am
by Carlo
Hello

Thanks for your reply. Basically i have both models: the old and the new mobo. Can you please tell me which 2 pins do you short at the switch? Alternatively can i use the same switch that comes with the remote cpu? Maybe its already shorted.

Another thing...the linear PSU has two 35v caps. Im feeling a little bulge on one of the Caps. Should i replace the caps?

regards

Carlo

Re: Replacement ATX PSU

PostPosted: Fri Feb 28, 2020 10:54 am
by Carlo
There is another pcb in the psu facing the linear power supply. It is encased in a metal plate. What is that for? Is that the 48v power supply? Does it have other purposes apart from 48v?

on the schematics there is no trace of this pcb. At least i couldn't find it.

Re: Replacement ATX PSU

PostPosted: Fri Feb 28, 2020 6:33 pm
by arjepsen
first - the atx switch pins:
there is a row of pins, right in front of the ide cable connectors (the connectors for the wide grey cable going to the harddisk)
Theres some small text in front of them, to let you know what they are. The two pins you would connect are the ones labeled: "ATX-SW". If you have an atx psu connected, shorting these two pins will start it up.
However, you don't want these two pins shorted constantly, 'cause like on a modern pc - if you hold the power button down for about 4-8 seconds, you're gonna force-shut-down...
Instead of using these pins, what I did was short two of the cables going from the psu to the board (IIRC - the green to any of the black). This means, anytime the psu gets main power, it will turn on. This means that all power supplies are still being turned on and off using the main switch on the cpu unit.

Second - the caps.
I'm uncertain - in my mind, the linear power supply IS the one on the side - the metal plate is the heatsink for this one. It's the one that provides 5V for the system.

Re: Replacement ATX PSU

PostPosted: Fri Feb 28, 2020 6:36 pm
by arjepsen
first - the atx switch pins:
there is a row of pins, right in front of the ide cable connectors (the connectors for the wide grey cable going to the harddisk)
Theres some small text in front of them, to let you know what they are. The two pins you would connect are the ones labeled: "ATX-SW". If you have an atx psu connected, shorting these two pins will start it up.
However, you don't want these two pins shorted constantly, 'cause like on a modern pc - if you hold the power button down for about 4-8 seconds, you're gonna force-shut-down...
Instead of using these pins, what I did was short two of the cables going from the psu to the board (IIRC - the green to any of the black). This means, anytime the psu gets main power, it will turn on. This means that all power supplies are still being turned on and off using the main switch on the cpu unit.

Second - the caps.
I'm uncertain - in my mind, the linear power supply IS the one on the side - the metal plate is the heatsink for this one. It's the one that provides 5V for the system.

Re: Replacement ATX PSU

PostPosted: Fri Feb 28, 2020 10:19 pm
by Carlo
Thanks for the info bro

Re: Replacement ATX PSU

PostPosted: Sat Feb 29, 2020 11:52 am
by arjepsen
Yw :-)