de.das.dude
Pro Indian Modder
- Joined
- Jun 13, 2010
- Messages
- 8,837 (1.70/day)
- Location
- Stuck in a PC. halp.
System Name | Monke | Work Thinkpad| Old Monke |
---|---|
Processor | Ryzen 5600X | Ryzen 5500U | FX8320 |
Motherboard | ASRock B550 Extreme4 | ? | Asrock 990FX Extreme 4 |
Cooling | 240mm Rad | Not needed | hyper 212 EVO |
Memory | 2x16GB DDR4 3600 Corsair RGB | 16 GB DDR4 3600 | 16GB DDR3 1600 |
Video Card(s) | Sapphire Pulse RX6700XT 12GB | Vega 8 | Sapphire Pulse RX580 8GB |
Storage | Samsung 980 nvme (Primary) | some samsung SSD |
Display(s) | Dell 2723DS | Some 14" 1080p 98%sRGB IPS | Dell 2240L |
Case | Ant Esports Tempered case | Thinkpad | Antec |
Audio Device(s) | Logitech Z333 | Jabra corpo stuff |
Power Supply | Corsair RM750e | not needed | Corsair GS 600 |
Mouse | Logitech G400 | nipple |
Keyboard | Logitech G213 | stock kb is awesome | Logitech K230 |
VR HMD | ;_; |
Software | Windows 10 Professional x3 |
Benchmark Scores | There are no marks on my bench |
This is a thread dedicated to check how the 12V and 5V cables are connected on your PSU and if it is actually a dual rail like the manufacturer claims it to be.
First a list of the tools you will need.
1. Tools:-
1.1 Multimeter
This doesnt not need to be those expensive ones. Heck, you can even do this with some wires and an LED light and a 3V cell.
Just in case you do get a multimeter, make sure it can measure at least 20V and has the connectivity testing feature which makes a *beep* if theres is a connecting path between the multimeter terminals
OR just use the resistance measuring mode.
"0" means no resistance = connected.
"1 with a left indent" means infinite resistance = not connected.
1.2 Tweezers
You will need this to short the 14th(green) and 16th(black) wire of the ATX motherboard connector to switch the PSU on manually.
Alternatively you can bend a suitable length of 1mm thick copper wire/ or a paper clip to do this.
1.3 Masking tape
not really used, but always good to keep this handy.
1.4 Wires
not used but good to keep it handy.
1.5 Anti static Gloves
in case youre on a carpet. or youre not grounded.
2. Now What to Do?
First of all. YOU DO NOT NEED TO OPEN YOU PSU FOR THIS!!! DONT TOUCH THAT SCREW DRIVER!
2.1 Disconnecting your PSU
1. Turn of your PC.
2. Turn off the power to the PSU (not the PSU switch)
3. There probably is some LED on you motherboard which goes off after you turn the power off. This means its safe to disconnect the PSU jacks from the mother board now.
4. Remove the power cable and screws connecting the PSU to the chassis and motherboard.
Note: do not switch on your PSU. You dont need the PSU powered on for this test.
2.2 Selecting correct multimeter mode
1. If there is a connectivity testing mode, select it. it looks like the symbol of a buzzer or has the symbol of a diode.
2. Alternatively select the resistance measuring mode. I use 2K ohm, which means it measures till 2K ohm.
2.3 The Concept behind this Test(please read)
The Meaning of "RAIL"
This is the long line of 12V and 5V cable that powers your peripherals like HDD, fans ODDs SSD, lights, and even powers GPUs etc. Each rail has a particular amount of max current that can flow through it. If more than that is required it will fry the transistors connected to that rail or simply wont supply enough power at all.
I has many rails
/ I has one rail
, what does that mean?
Multiple rails mean that the 12V and 5V are connected to different groups of transistors.
This means that all the 12V and 5V cables are not connected to the same "source" of power.
Which means that they may or may not allow the same amount current (and hence power) to each rail.
Having a single rain means that all the 12v and 5v lines originate from the same source.
Even if you have two physically visible rails, they maybe connected to the same source meaning there's actually one rail. (manufacturer just lied to you)
Thus even if the manufacturer specifies max 18A and 17A for the 12V two rails, since they are connected to the same source, either of the rails can carry the total of 18+17 = 35A irrespective of what the manufacturer claims.
However if there are two distinct rails whose max currents are 12A and 40A respectively,
they will allow only what is specified. connect your GPU to the 12A rail and get ready to tear your hair off
(actually there wont be any GPU connector on the 12V rail
)
Is there any way i can know which one i have?
Fortunately, im here to the rescue. This tutorial will show you how to know if you have one rail or multiple rails or if the manufacturer just lied to you.
THE BASIC CONCEPT.
If two things are connected to the same thing (i.e single rail) then they are connected to each other.
In other words, for a single rail PSU all the wires of a same voltage are connected by conducting paths. Hence all the wires are "equal".
3. Just When You Thought I wont Write about the Real Test...
okay time to get your hands dirty ! (not really
)
3.1 The Easy But not Very Scientific Way
1. Simply look at the ampere rating for the two "rails".
2. If they are almost the same value with a max tolerance of 2A, like 18A and 17 A, 25A and 23A, it probably is a single rail, just two different set of wires.
3. If theres is a huge difference between the ampere ratings like 18A and 25A, they sure belong to different rails.
3.2 The Scientific way
Its time to finally get your multimeter.
First lets test the peripheral rails, the ones with one yellow, one orange/red and two black wires.
We will test only the 12V rail as 5V really doesnt matter, 12V takes the real punch.
1. Insert the black multimeter terminal into one yellow wire's molex pin of one rail.
2. Insert the red terminal into the yellow wire's molex pin of another terminal.
If multimeter in connectivity testing mode:-
If you get beep, it means that both "rails" are connected to the same rail. Which means the PSU is single rail.
If no beep, they are individual rails.
If multimeter in resistance measuring mode
If your multimeter shows anything less than 100 Ohms resistance, then both "rails" are connected to the same rail. Which means the PSU is single rail.
If your multimeter shows infinity or "1" with a left indent, it means that the rails are different.
3.3 The Ghetto Scientific way (for those without a multimeter)
1. Take two wires of 6" length.
2. Strip both ends for both the wires. Strip off around 1/2".
Lets name the wires A and B.
3. Take one end of wire A and jam it into the yellow wire's molex pin. Take the other end and connect it to the positive or longer leg of the LED. Just wrap around the naked wire around the LED leg and use masking tape to hold in place.
4. Take one end of wire B and jam it into the yellow wire's molex pin of another rail. take the other and connect it to the positive of the 3V battery/cell. Use plenty of masking tape as required.
5. Now take the free end of the LED and touch it to the negative terminal of the battery.
IF the LED glows, its single rail. If not its two distinct rails.
Note: Best 3V battery?? Your old BIOS battery!
3.4 Moving Forward
Now that you have tested the peripheral rails, next you need to check the CPU ATX 4 or 8 pin power rail.
You may want to check:-
1. The power rail with the peripheral rail.
2. Individual 12V wires of the power rail i.e. if all the 12V power jack wires come from same source or not.
4. How to Strip your PSU and find out if its Single or Dual Rail
4.1 Safely Switching off your PSU. damnit i dont have a camera and cant finish![Frown :( :(](https://tpucdn.com/forums/data/assets/smilies/frown-v1.gif)
finishing soon....
how to open up the PSU and find out if its a single or dual rail!
so youre gonna thank me or not
?
i didt copy paste, i had to write this whole thing you know..... ^_^
[taking pics and generating drawings, will put them up soon!]
First a list of the tools you will need.
1. Tools:-
- A multimeter(specification afterwards)
- tweezers
- some masking tape
- some spare wires
- anti static gloves
1.1 Multimeter
This doesnt not need to be those expensive ones. Heck, you can even do this with some wires and an LED light and a 3V cell.
![](/forums/proxy.php?image=http%3A%2F%2Fimg.techpowerup.org%2F110617%2F220px-Digital_Multimeter_Aka.jpg&hash=82d7026fc49e7c814ee9a067d91a8585)
Just in case you do get a multimeter, make sure it can measure at least 20V and has the connectivity testing feature which makes a *beep* if theres is a connecting path between the multimeter terminals
OR just use the resistance measuring mode.
"0" means no resistance = connected.
"1 with a left indent" means infinite resistance = not connected.
1.2 Tweezers
You will need this to short the 14th(green) and 16th(black) wire of the ATX motherboard connector to switch the PSU on manually.
Alternatively you can bend a suitable length of 1mm thick copper wire/ or a paper clip to do this.
1.3 Masking tape
not really used, but always good to keep this handy.
1.4 Wires
not used but good to keep it handy.
1.5 Anti static Gloves
in case youre on a carpet. or youre not grounded.
2. Now What to Do?
First of all. YOU DO NOT NEED TO OPEN YOU PSU FOR THIS!!! DONT TOUCH THAT SCREW DRIVER!
2.1 Disconnecting your PSU
1. Turn of your PC.
2. Turn off the power to the PSU (not the PSU switch)
3. There probably is some LED on you motherboard which goes off after you turn the power off. This means its safe to disconnect the PSU jacks from the mother board now.
4. Remove the power cable and screws connecting the PSU to the chassis and motherboard.
Note: do not switch on your PSU. You dont need the PSU powered on for this test.
2.2 Selecting correct multimeter mode
1. If there is a connectivity testing mode, select it. it looks like the symbol of a buzzer or has the symbol of a diode.
![](/forums/proxy.php?image=http%3A%2F%2Fimg.techpowerup.org%2F110617%2Fconticon1.jpg&hash=f13ec482e5c4e9d34e44122d89fbe4c1)
2. Alternatively select the resistance measuring mode. I use 2K ohm, which means it measures till 2K ohm.
2.3 The Concept behind this Test(please read)
The Meaning of "RAIL"
This is the long line of 12V and 5V cable that powers your peripherals like HDD, fans ODDs SSD, lights, and even powers GPUs etc. Each rail has a particular amount of max current that can flow through it. If more than that is required it will fry the transistors connected to that rail or simply wont supply enough power at all.
I has many rails
![Big Grin :D :D](https://tpucdn.com/forums/data/assets/smilies/biggrin-v1.gif)
![Frown :( :(](https://tpucdn.com/forums/data/assets/smilies/frown-v1.gif)
Multiple rails mean that the 12V and 5V are connected to different groups of transistors.
This means that all the 12V and 5V cables are not connected to the same "source" of power.
Which means that they may or may not allow the same amount current (and hence power) to each rail.
Having a single rain means that all the 12v and 5v lines originate from the same source.
Even if you have two physically visible rails, they maybe connected to the same source meaning there's actually one rail. (manufacturer just lied to you)
Thus even if the manufacturer specifies max 18A and 17A for the 12V two rails, since they are connected to the same source, either of the rails can carry the total of 18+17 = 35A irrespective of what the manufacturer claims.
However if there are two distinct rails whose max currents are 12A and 40A respectively,
they will allow only what is specified. connect your GPU to the 12A rail and get ready to tear your hair off
![Big Grin :D :D](https://tpucdn.com/forums/data/assets/smilies/biggrin-v1.gif)
![Stick Out Tongue :p :p](https://tpucdn.com/forums/data/assets/smilies/tongue-v1.gif)
Is there any way i can know which one i have?
Fortunately, im here to the rescue. This tutorial will show you how to know if you have one rail or multiple rails or if the manufacturer just lied to you.
THE BASIC CONCEPT.
If two things are connected to the same thing (i.e single rail) then they are connected to each other.
In other words, for a single rail PSU all the wires of a same voltage are connected by conducting paths. Hence all the wires are "equal".
3. Just When You Thought I wont Write about the Real Test...
okay time to get your hands dirty ! (not really
![Frown :( :(](https://tpucdn.com/forums/data/assets/smilies/frown-v1.gif)
3.1 The Easy But not Very Scientific Way
1. Simply look at the ampere rating for the two "rails".
2. If they are almost the same value with a max tolerance of 2A, like 18A and 17 A, 25A and 23A, it probably is a single rail, just two different set of wires.
3. If theres is a huge difference between the ampere ratings like 18A and 25A, they sure belong to different rails.
3.2 The Scientific way
Its time to finally get your multimeter.
First lets test the peripheral rails, the ones with one yellow, one orange/red and two black wires.
We will test only the 12V rail as 5V really doesnt matter, 12V takes the real punch.
1. Insert the black multimeter terminal into one yellow wire's molex pin of one rail.
2. Insert the red terminal into the yellow wire's molex pin of another terminal.
If multimeter in connectivity testing mode:-
If you get beep, it means that both "rails" are connected to the same rail. Which means the PSU is single rail.
If no beep, they are individual rails.
If multimeter in resistance measuring mode
If your multimeter shows anything less than 100 Ohms resistance, then both "rails" are connected to the same rail. Which means the PSU is single rail.
If your multimeter shows infinity or "1" with a left indent, it means that the rails are different.
3.3 The Ghetto Scientific way (for those without a multimeter)
1. Take two wires of 6" length.
2. Strip both ends for both the wires. Strip off around 1/2".
Lets name the wires A and B.
3. Take one end of wire A and jam it into the yellow wire's molex pin. Take the other end and connect it to the positive or longer leg of the LED. Just wrap around the naked wire around the LED leg and use masking tape to hold in place.
4. Take one end of wire B and jam it into the yellow wire's molex pin of another rail. take the other and connect it to the positive of the 3V battery/cell. Use plenty of masking tape as required.
5. Now take the free end of the LED and touch it to the negative terminal of the battery.
IF the LED glows, its single rail. If not its two distinct rails.
Note: Best 3V battery?? Your old BIOS battery!
3.4 Moving Forward
Now that you have tested the peripheral rails, next you need to check the CPU ATX 4 or 8 pin power rail.
You may want to check:-
1. The power rail with the peripheral rail.
2. Individual 12V wires of the power rail i.e. if all the 12V power jack wires come from same source or not.
4. How to Strip your PSU and find out if its Single or Dual Rail
4.1 Safely Switching off your PSU. damnit i dont have a camera and cant finish
![Frown :( :(](https://tpucdn.com/forums/data/assets/smilies/frown-v1.gif)
finishing soon....
how to open up the PSU and find out if its a single or dual rail!
so youre gonna thank me or not
![Stick Out Tongue :p :p](https://tpucdn.com/forums/data/assets/smilies/tongue-v1.gif)
i didt copy paste, i had to write this whole thing you know..... ^_^
[taking pics and generating drawings, will put them up soon!]
Last edited: