Spare PSU

[Hugh54321]

I have two PSU collecting dust. I saw ATX breakout boards on amazon so I thought maybe I could make my own. Put a current meter on each rail it and some USB charging ports. Some fuses too. Is there any issue with using a PSU like this? I don't think I will use the 3 or 12V rails for anything. Maybe in summer I will use the 12V rail to run a fan.

[WH2002]

you will need to join the graan wire to one of the black wires to make it tun on, you will also need to add either a resistor or lamp on one of the rails to make sure that there is always a load on the psu.

if you just search for pc power supply mod you will find hundreds of guides about how you need to do this.

[Suppersupport]

11 minutes ago, I7 5820K said:

you will need to join the graan wire to one of the black wires to make it tun on, you will also need to add either a resistor or lamp on one of the rails to make sure that there is always a load on the psu.

if you just search for pc power supply mod you will find hundreds of guides about how you need to do this.

do what he said but I would suggest a breaker or more likely a fuse and connect the grean wire to a ground with a switch.

[Unimportant]

38 minutes ago, Hugh54321 said:

Is there any issue with using a PSU like this? I don't think I will use the 3 or 12V rails for anything. Maybe in summer I will use the 12V rail to run a fan.

It depends on the PSU in question. More expensive higher end PSU's create a single 12V in the flyback section, which is then further converted to 5V and 3.3V using DC/DC converters. On such a PSU you can use the 5V rails and leave the 12V unused without problems.

 

Other PSU's however, create all rails in the flyback section, but only a single rail can be used for regulation. This is usually the 12V rail. Using only the 5V rail in such a PSU, without using the 12V rail, might cause poor regulation on said 5V line.

[Hugh54321]

8 minutes ago, Unimportant said:

It depends on the PSU in question. More expensive higher end PSU's create a single 12V in the flyback section, which is then further converted to 5V and 3.3V using DC/DC converters. On such a PSU you can use the 5V rails and leave the 12V unused without problems.

 

Other PSU's however, create all rails in the flyback section, but only a single rail can be used for regulation. This is usually the 12V rail. Using only the 5V rail in such a PSU, without using the 12V rail, might cause poor regulation on said 5V line.

ok so I need to dust the PSU off and see if they have DC converters. Thanks.