Hotwiring a PSU

[SithSolo1]

I know if you use a wire to connect the green wire on the ATX connector to one of the black ones that the PSU will indeed power on but I have some questions:

Is it safe to do this?

For instance could I fill/test a water cooling setup this way or would it dmg the pumps?

 

[PurdueRy]

It's perfectly safe to do.

 

[Fullmetal Chocobo]

Iti s perfectly safe to do this. The only you might run in to with older PSUs is load balancing. I ran my dual Xeon 2.66 with two PSUs with the second PSU hardwared to a switch. Worked absolutely great.

 

[skillyho]

What's the best way to manufacturer a cable to safely do something like this? I've seen paper-clips used before....I have a feeling that's not too safe.

 

[Fullmetal Chocobo]

Originally posted by: BSkip22
What's the best way to manufacturer a cable to safely do something like this? I've seen paper-clips used before....I have a feeling that's not too safe.

It safe so long as the paperclip doesn't touch your case (thus ground) while it's operating. You can touch the paperclip while your PSU is powered -- there is only a signal going through it, no power. The bad thing about using a paperclip is that it is incredibly inconvenient.

I have done the switch several different ways now, and my favorite way is to get a 24p connecot (usually robbing it from a ATX 24-pin extension), pull all the wires out using a pin extractor with the exception of the green cable and a black cable. These I cut about 6-12" down, and strip the ends. I then solder more cable (doesn't have to be thick cable at all--once again, this is a signal) that goes to a toggle switch mounted into a bay cover on the front of my case. (BTW, do all soldering when the power supply is unplugged & turned off, just in case).

Once the switch is tested to make sure it works and also to find the normally off / normally on positions, it is good to go. I went from this point, and wired several fans and cold cathode lights to the remaining +12v (yellow) lines not being used on the 24-pin ATX connector. It is a simple matter of putting the cables back in the connector, then soldering either 3-pin fan connectors or 4-pin molex connectors (with no +5V or secondary ground) to a yellow & black pair. I also did the same with left over 4-pin, 6-pin, and 8-pin +12v connectors. 🙂


PICS:

Here is a pic of the modded 8-pin connector

You can see the modded 24-pin coming from the top PSU

A bit closer view of the modded 24-pin connector

A much older mod job, where the connector was cut, soldered, then taped up. It looks much better modding a 24-pin extension, not to mention you leave the original PSU intact.

 

[myocardia]

Originally posted by: BSkip22
What's the best way to manufacturer a cable to safely do something like this? I've seen paper-clips used before....I have a feeling that's not too safe.

The easiest way, by far, is to just strip the wires well above the ATX connector, then solder some wires to them, then heatshrink over the soldered joints. After that, just run the wires you've attached to a switch.

 

[SithSolo1]

Or if you are cheap just use some 18ga speaker wire you have sitting around like I did.

 

[xylem]

Originally posted by: Fullmetal Chocobo

Originally posted by: BSkip22
What's the best way to manufacturer a cable to safely do something like this? I've seen paper-clips used before....I have a feeling that's not too safe.

It safe so long as the paperclip doesn't touch your case (thus ground) while it's operating.

It's fine to touch the case with it, if it's on... basically the same as one of the black wires (ground).