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Dual PSU How-Tos

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I have one major problem with using another power supply. My second powersupply only powers my fans.

It's a 300w supply. At first, it worked fine. It stayed on unless otherwise. But recently it's been working wierd. It randomly shuts off. I mean random like sometimes it will run for 20min and sometimes it will run 3min.

I built a rocker switch using the green and black lines to create a switch. So i use that to turn on and off.

As im typing this tread, the second PSU shakes and rattles. I mod the PSU fan switching it with a led fan so i know if its on or not. The led fan runs about 2500rpm but from what I see is it runs alot slower.

Is there any reason why my PSU turns off? And why the fan runs on low speeds?
 
Welcome to the forums.
From the sound of it, the second PSU may be on the way out. Random shutdowns of a PSU are usually a sign of impending failure.
 
If anybody in this forum has success with using a 2nd PSU, you are very lucky. For me, I am not one of them.

I use my 2nd PSU just to power my fans and it only takes up the 12v grid lines which consumes about 1 watt per fan. I have six fans running on the 12v line consuming 12 watts out of my 300 watt PSU.

Some PSU doesn't have "Minimal Load" which will be fine for others running their hard drive or optical drives using their 2nd PSU.

Now, for my solution for my dilemma. I need a POWER SUPPLY LOAD RESISTOR which can be bought for $10 at cyberguys.com.
This takes up the 5.5v line which acts as a dummy load taking up a total of 1 amp. This will be enough to satisfy my PSU's "MINIMAL LOAD".

Note: If you are like me, using a 2nd PSU "just" to power chasis fans, not all PSUs are all the same. If you connect the green to the black wire, it may cause your PSU to fry or even explode. Proceed with absolute caution. The POWER SUPPLY LOAD RESISTOR is 100% percent safe (according to their ad) to function for your PSU. But the dummy load gets really hot so put it in a good safe cool place where nobody can easily get access to the dummy load.
 
FireMogle said:
Didnt this use to be a sticky?
Yes, but there seems to be some debate as to its necessity. Requests to the mods to resticky it are greatly appreciated.
 
OK, something wierd just happen (a good thing).

I reconnect 2 of my cathode tube (12v) to my second PSU including 3 led fans last night without connecting a DUMMY LOAD for the 5v line.

I guess I forgot to shut down the second PSU and left it over night. When I woke up, to my suprise, the second PSU is still running!

Does that mean, my 2 cathode tubes is enough to satisfy my MINIMUM LOAD on the 12v line? I thought I need to satisfy my 5v line, not my 12v? WIERD!
 
ValcristDK said:
OK, something wierd just happen (a good thing).

I reconnect 2 of my cathode tube (12v) to my second PSU including 3 led fans last night without connecting a DUMMY LOAD for the 5v line.

I guess I forgot to shut down the second PSU and left it over night. When I woke up, to my suprise, the second PSU is still running!

Does that mean, my 2 cathode tubes is enough to satisfy my MINIMUM LOAD on the 12v line? I thought I need to satisfy my 5v line, not my 12v? WIERD!

I have let PSU's run for days on end with no load on the 5v... or no load on teh 12...
 
Done the same. For a while, I had no load at all on the 2nd PSU, and have never experienced any problem.
 
I delete the old bump. Until its stickied again, I don't see any reason to keep increasing the post amount.
 
awesome thnx for all the nfo im going to have to try that out if i keep adding junk to my PC.
 
THIS SHOULD BE A STICKY!!!

As a newbie I was just about to ask this question in that i wll soon be having a Raid 1 array (for safe files storage) and fear my 350W psu will not be able to support everything (its a miracle as it is) I have a extra 300W just laying around, why not us it?
 
berserker said:
THIS SHOULD BE A STICKY!!!

As a newbie I was just about to ask this question in that i wll soon be having a Raid 1 array (for safe files storage) and fear my 350W psu will not be able to support everything (its a miracle as it is) I have a extra 300W just laying around, why not us it?

WELCOME TO THE FORUMS...!!!

BUMP BUMP BUMP, ...BUMPITY - BUMP..!!
:D
 
awesome when my dual operton phase change is up ill shot pics of it, cause im doing dual PSU of Antec True, wow thnx this is going to rock!
 
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