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- NH Biodiesel master
Bump for a confirmation to my question
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Dual PSU How-Tos
- Thread starter stool
- Start date
- Joined
- Nov 16, 2003
- Location
- Cleveland OHIO
i beleive so? dont hold me responsable, i used to just have a second switch to power my second PSU on
- Joined
- May 30, 2005
- Location
- Niagara Falls, Ontario
just have a relay to switch the AT psu on when it gets the 12V signal from teh ATX
Which method?
Ok, so I want to add a 300W standard PSU to my rig that has already got a 400W Coolermaster PSU. I'm doing this because I need more juice on my 12V rail, the Coolermaster PSU only supplies 19A through it, the 300W PSU pumps 15A through the 12V rail.
Now my question is: which method would be the best one to use in my case? I kinda prefer a safe one without many materials and without much hassle such as soldering and stuff.
Ok, so I want to add a 300W standard PSU to my rig that has already got a 400W Coolermaster PSU. I'm doing this because I need more juice on my 12V rail, the Coolermaster PSU only supplies 19A through it, the 300W PSU pumps 15A through the 12V rail.
Now my question is: which method would be the best one to use in my case? I kinda prefer a safe one without many materials and without much hassle such as soldering and stuff.
- Joined
- Dec 7, 2003
Just understand the math, its NOT like now you will have 19A + 15A = 34A of 12V power.
If you only have like 1 fan, 1 hard drive, and 1 optical drive, the 12V draw off your main coolermaster is probably only 1-2A, so adding a second psu will spare you only these 1-2A. If you've got a lot a drives etc, their draw can become increasingly significant.
My personal opinion is I would definitely go with the 5V relay method. Any method except a 2nd switch is going to require basic wiring and pinning, etc. The 5V relay method is nice because it doesn't require an additional adaptor on the main ATX power connector.
If you're not up to putting it together, or can't friend who will, I'll be happy to build you one, but you'll have to contact me by pm.
navig
If you only have like 1 fan, 1 hard drive, and 1 optical drive, the 12V draw off your main coolermaster is probably only 1-2A, so adding a second psu will spare you only these 1-2A. If you've got a lot a drives etc, their draw can become increasingly significant.
My personal opinion is I would definitely go with the 5V relay method. Any method except a 2nd switch is going to require basic wiring and pinning, etc. The 5V relay method is nice because it doesn't require an additional adaptor on the main ATX power connector.
If you're not up to putting it together, or can't friend who will, I'll be happy to build you one, but you'll have to contact me by pm.
navig
OP
- Joined
- Dec 20, 2000
- Location
- Albany, NY
- Thread Starter
- #226
- Joined
- May 15, 2004
- Location
- Ohio
I have a question reguarding these very informative articles. I have 2 good power supplies. I have them running the same system, one powering the MB and CPU the other powering everything else. However the slave PSU i have running the drives and fans will not stay on unless it is connected to another MB. (If i short the pin 14 and a ground it will start and then shut-off.) I have tried connecting the pin 7 and 8 together to ground the power on OK. The also does not work, the PSU unit will turn on for about 1 sec, maybe less. What i did to remedy this, was strip an old MB of everything. I plug the ATX connector from the slave PSU and power it up. With this set up everything works and I am able to run my system, but i have to have two MB right next to each other. What I am doing wrong in this, how can i keep the slave PSU powered up, without plugging it into an empty MB? Any ideas that anyone has would be helpful, if you need more info let me know.
OP
- Joined
- Dec 20, 2000
- Location
- Albany, NY
- Thread Starter
- #228
There are some odd PSUs that won't work correctly when they are jumpered. I don't actually think there is much you can do about it except get a different PSU
- Joined
- Jul 27, 2005
- Location
- Austin, Texas
Yah tell me about it, I found the hard way. I was trying to do a permamant setup and cut wires and made room in my case for the slave, and then all happy, but then it did not work. what happens is if I turn the main psu on the slave stays off but draws power from the main. And if I turn the slave on first, the main is off and drws power from the slave. They just dont work together. I did everything according to the sticky and the articles ,no good. I thing what happens is there is a mechanism that when one is on the other is forced to shut down.
Both are ATX, one 350 and the other an old 250 watts. Its a shame, I was going to increase my 12v rail amp by 9 amp and the 3.5v by 16 and 5 v by 25 amps. could have gotten me a 600 watts and saveed me a lot of headaches.
Both are ATX, one 350 and the other an old 250 watts. Its a shame, I was going to increase my 12v rail amp by 9 amp and the 3.5v by 16 and 5 v by 25 amps. could have gotten me a 600 watts and saveed me a lot of headaches.
i also have a few questions... i have an extra 350w max power supply from a really old computer. when i get my watercooling, i want to run the pump exclusively off that psu(or if it plugs into a wall?? dont know, D5 from danger den).
do i still need to do all this stuff or can i just jumper the 20 pin to get it to turn on?
do i still need to do all this stuff or can i just jumper the 20 pin to get it to turn on?
- Joined
- Nov 16, 2003
- Location
- Cleveland OHIO
you could jsut jumper it.
i dont know what the big deal about the auto switching is. When i did mine, i just got a big on/off switch from rat shack, and ran wires from the pins to that. so if i wanted to turn on just my fans/lights/whatever to make sure everything was working..then turn on the rest of the pc. OR, id let the fans cool it down after it was off, th en shut everything off..i saw no big deal
i dont know what the big deal about the auto switching is. When i did mine, i just got a big on/off switch from rat shack, and ran wires from the pins to that. so if i wanted to turn on just my fans/lights/whatever to make sure everything was working..then turn on the rest of the pc. OR, id let the fans cool it down after it was off, th en shut everything off..i saw no big deal
- Joined
- Nov 16, 2003
- Location
- Cleveland OHIO
easiest road is my road lol. i have that fear of blowing stuff up too im not gona wire 2 psus together..ive blown those things up before, quite a site to remember!
- Joined
- Dec 7, 2003
I'm not certain what all the confusion is. The wiring is about as simple as it gets. Even in my more complicated scheme with a 5V relay, all I'm doing is using the power from the master power supply to act as a way to jump the power-on pins of the slave psu.
There seems to be some continuing confusion. We are not advocating wiring together two power supplies! The amps do NOT combine. We are just illustrating a simple way to have a second power supply jump to on as soon as the primary supply is turned on.
There seems to be some continuing confusion. We are not advocating wiring together two power supplies! The amps do NOT combine. We are just illustrating a simple way to have a second power supply jump to on as soon as the primary supply is turned on.
- Joined
- Dec 7, 2003
And that's the totally appropriate use for such a setup. On one of my systems, I have a $12 350W to power about 10 fans, 3 hard drives, and 2 optical drives.
Just take a peek at this labeled pic:
The black 4 pin molex connects to any available 4 pin power plug from the master psu. When you punch the on button on your computer, the main psu power up. Power enters the black 4 pin molex, and hits the relay switch--the 5V power causes the relay to switch to "closed", thus closing the circuit which jumps the green and black cables of the slave psu--which now powers on.
When you turn off the computer, the main psu turns off, the relay switch loses power, and the green and black cables of the slave psu "unjump", turning it off.
If you're not comfortable putting these cables together, I'd be happy to do it for you (no profit), but you'll need to contact me via pm.
navig
Just take a peek at this labeled pic:
The black 4 pin molex connects to any available 4 pin power plug from the master psu. When you punch the on button on your computer, the main psu power up. Power enters the black 4 pin molex, and hits the relay switch--the 5V power causes the relay to switch to "closed", thus closing the circuit which jumps the green and black cables of the slave psu--which now powers on.
When you turn off the computer, the main psu turns off, the relay switch loses power, and the green and black cables of the slave psu "unjump", turning it off.
If you're not comfortable putting these cables together, I'd be happy to do it for you (no profit), but you'll need to contact me via pm.
navig
where do you connect the 20 pin connector to? i konw it says slave, but neither of my psu's have removable thingys on the back(cant think of the exact word). in other words, i cant remove any wires.
ohh, are those adapters? where do i need to get the adapters and wires from?
ohh, are those adapters? where do i need to get the adapters and wires from?
- Joined
- Dec 7, 2003
That particular adaptor is ready to plug into any 2 power supplies. My mostly empty 20pin male plugs into the end of your slave's 20pin female connector (remember you're not using this--the master psu supplies motherboard power).
See here:
The Master psu is the modular X connect. I have it jumped with a paperclip rather than plugged into a motherboard. The multicolor fan psu on the desk is the slave.
I took an ATX 20pin extender cable ($5) and pulled out all the cables except the green and a ground on the male side. Actually you could probably pick up the plentiful 20 to 24pin adaptors for even cheaper.
You can salvage any male 4 pin connector, and save the 5V line (red) and ground.
The 5V relay can be picked up from Radioshack for $3.
Solder and heatshrink.
See here:
The Master psu is the modular X connect. I have it jumped with a paperclip rather than plugged into a motherboard. The multicolor fan psu on the desk is the slave.
I took an ATX 20pin extender cable ($5) and pulled out all the cables except the green and a ground on the male side. Actually you could probably pick up the plentiful 20 to 24pin adaptors for even cheaper.
You can salvage any male 4 pin connector, and save the 5V line (red) and ground.
The 5V relay can be picked up from Radioshack for $3.
Solder and heatshrink.
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