Overclock.net › Forums › Components › Power Supplies › A few questions about Power Supplies
New Posts  All Forums:Forum Nav:

A few questions about Power Supplies

post #1 of 3
Thread Starter 
I'm not sure if I'll be able to get the answers that I'm looking for as they are partially design type questions, but I thought I'd ask anyways.

I was wondering why computer power supply manufacturers use multiple wires to deliver the same voltage level to a device. My own theory is that they do this to allow them to spread the current draw across multiple wires, which allows them to decrease the size of them, rather then using one large cable rated for 30Amps+.

Example of this would be the pci-e power connector, where there are 3 separate 12V connections.

Building ontop of that assumption/question leads me into multi-rail power supplies. In the case of this, do power supply manufacturers ever use multi-rails in the same connector (the 3 12V in the same pci-e power connector) or do they run the multiple rail in separate connectors (2 pci-e power connectors to a gpu would have 1 rail in one pci-e power connector and a second rail in the other pci-e power connector).

Thanks for any insight people may be able to provide as if my theoretical views are correct, my device may have become simplified, which means should be cheaper to build and able to sell it at a lower price point.
post #2 of 3
Your assumption makes sense as 16 guage wire is rated for a max of 10 amps by the national electrical code. As for the separate rails put together I think it varies by manufacturer. Though twin rail PSUs are not very common anymore. As now it is easier just to make a larger single rail with the same current capability as the twin rail. It becomes a kind of redundancy that if one rail fails the second can sustain the system.
Sandy Thunder
(18 items)
 
QuickSilver X1
(15 items)
 
 
CPUMotherboardGraphicsRAM
i7-3930k C1 4.6GHz @1.344v Sabertooth X79 2x EVGA GTX 560 Ti SC SLI 900/2106 Dominator 1866 16GB 9-10-9-27 
Hard DriveHard DriveCoolingOS
Crucial M4 64GB 'Cuda 320GB XSPC Rasa 750 RX240 push/pull + Alphacool UT60 ... Win 7 Pro x64 
MonitorMonitorMonitorKeyboard
Asus VE198D 19" Samsung 920NW 19" Samsung 906BW 19" Logitech G510s 
PowerCaseMouseMouse Pad
Corsair HX850M Carbide 400R Cyborg M.M.O. 7 Corsair MM200 
AudioOther
Bose Music Monitor Nuforce Icon HDP 
CPUMotherboardGraphicsRAM
Phenom II x6 1090T BE Sabertooth 990FX Radeon HD 5770 1GB Corsair Veangence Blue 
Hard DriveOptical DriveCoolingOS
WD Caviar Black 1TB  Lite ON 16x DVD-R/RW ThermalRight Silver Arrow Windows 7 Professional 64 bit 
MonitorKeyboardPowerCase
Syncmaster 921BW 19" & Syncmaster 965 19" and S... Apple aluminum wired keyboard Corsair TX650 Silverstone TJ05 with window and thermal contro... 
MouseMouse PadAudio
logitech mx air None Monsoon MM-700 
  hide details  
Reply
Sandy Thunder
(18 items)
 
QuickSilver X1
(15 items)
 
 
CPUMotherboardGraphicsRAM
i7-3930k C1 4.6GHz @1.344v Sabertooth X79 2x EVGA GTX 560 Ti SC SLI 900/2106 Dominator 1866 16GB 9-10-9-27 
Hard DriveHard DriveCoolingOS
Crucial M4 64GB 'Cuda 320GB XSPC Rasa 750 RX240 push/pull + Alphacool UT60 ... Win 7 Pro x64 
MonitorMonitorMonitorKeyboard
Asus VE198D 19" Samsung 920NW 19" Samsung 906BW 19" Logitech G510s 
PowerCaseMouseMouse Pad
Corsair HX850M Carbide 400R Cyborg M.M.O. 7 Corsair MM200 
AudioOther
Bose Music Monitor Nuforce Icon HDP 
CPUMotherboardGraphicsRAM
Phenom II x6 1090T BE Sabertooth 990FX Radeon HD 5770 1GB Corsair Veangence Blue 
Hard DriveOptical DriveCoolingOS
WD Caviar Black 1TB  Lite ON 16x DVD-R/RW ThermalRight Silver Arrow Windows 7 Professional 64 bit 
MonitorKeyboardPowerCase
Syncmaster 921BW 19" & Syncmaster 965 19" and S... Apple aluminum wired keyboard Corsair TX650 Silverstone TJ05 with window and thermal contro... 
MouseMouse PadAudio
logitech mx air None Monsoon MM-700 
  hide details  
Reply
post #3 of 3
Thread Starter 
I was thinking that as well, from a theoretical and fundamental view point of how they would deal with large current loads while keeping the wire size relatively small. I really do hope this is this case as I could have (in my example) the three 12V wires come together, measure the current going through them on (my current chips are rated to measure up to 50Amps) then split them back to three wires to go to the device it is powering. Would reduce down the parts and simplify the design if that's how its actually designed.
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Power Supplies
Overclock.net › Forums › Components › Power Supplies › A few questions about Power Supplies