Power Supply Amperage Question

[omalley]

Hello, I need some help about PSUs Amps. I have a 600 Watt, 700 Watt, and 850 Watt PSU. And the label on all 3 look different on how they display the Amps.

The 600 shows
|+12v1|+12v2|
| 25A | 25A |

700
|+12v1|+12v2|+12v3|+12v4|
| 18A | 18A | 18A | 18A |

850
|+12v|
| 70A |

So what is the difference in the charts? And is the +12v only on the PCIe cables or every cable?

Also is the 700 Watt able to run a single GTX 580 since the 580 takes 42 Amps? With a 125 Watt CPU. AMD Phenome II x4 945 or 955?

Thanks!

 

[rolli59]

The 600 watt has dual rails each capable individually of 25 amps, usually there is a total combined wattage stated for those as well which then wattage/12volts = total combined Amps
700 has quad +12 volt rails same explanation as above.
the 850 single large +12 volt rail
Every cable on the PSU that has a yellow wire in it is carrying +12volts.
Yes the 700 will run a GTX580 if the combined amps meet the 42 amp requirement which is for the total system not just the GPU.

 

[omalley]

The total Amps on the 700 Watt is 72 which is more then my 850? =/
But then that means the 700 will have 30 Amps left to power everything else since the GTX 580 can use 42.
I was thinking I meant that each PCIe cable only carried 18A which of made the GTX 580 only get 36 Amps but I guess I'm wrong lol.

 

[rolli59]

The total Amps on the 700 Watt is 72 which is more then my 850? =/
But then that means the 700 will have 30 Amps left to power everything else since the GTX 580 can use 42.
I was thinking I meant that each PCIe cable only carried 18A which of made the GTX 580 only get 36 Amps but I guess I'm wrong lol.

Total amps is not adding all those individual rails together!! Many that PSU probably has 500-600watts allotted to the +12 volt rails so amps would be 600/12= 50amps total although each rail can individually provide 18amps they can not all at the same time!
GTX580 does not use 42 amps, it is recommended to have a PSU capable of providing total of 42 amps on the +12 volts to provide all the components in the system with +12 volt power. The GTX uses around 260 watts under load which is only 21-22 amps http://www.guru3d.com/articles_pages/geforce_gtx_580_review,7.html

Graphics card power distribution is
The PCIe slot gives 75 watts = 6.25amps
6 pin PCIe power connector 75 watts = 6.25 amps
8 pin PCIe power connector 150 watts = 12.5 amps

 

[omalley]

The total Amps on the 700 Watt is 72 which is more then my 850? =/
But then that means the 700 will have 30 Amps left to power everything else since the GTX 580 can use 42.
I was thinking I meant that each PCIe cable only carried 18A which of made the GTX 580 only get 36 Amps but I guess I'm wrong lol.

Total amps is not adding all those individual rails together!! Many that PSU probably has 500-600watts allotted to the +12 volt rails so amps would be 600/12= 50amps total although each rail can individually provide 18amps they can not all at the same time!
GTX580 does not use 42 amps, it is recommended to have a PSU capable of providing total of 42 amps on the +12 volts to provide all the components in the system with +12 volt power. The GTX uses around 260 watts under load which is only 21-22 amps http://www.guru3d.com/articles_pages/geforce_gtx_580_review,7.html

Graphics card power distribution is
The PCIe slot gives 75 watts = 6.25amps
6 pin PCIe power connector 75 watts = 6.25 amps
8 pin PCIe power connector 150 watts = 12.5 amps

Okay thank you. =)
And the 850 should be able to handle 2 gtx 670s 4gb and a OC fx 6350?

 

[rolli59]

The total Amps on the 700 Watt is 72 which is more then my 850? =/
But then that means the 700 will have 30 Amps left to power everything else since the GTX 580 can use 42.
I was thinking I meant that each PCIe cable only carried 18A which of made the GTX 580 only get 36 Amps but I guess I'm wrong lol.

Total amps is not adding all those individual rails together!! Many that PSU probably has 500-600watts allotted to the +12 volt rails so amps would be 600/12= 50amps total although each rail can individually provide 18amps they can not all at the same time!
GTX580 does not use 42 amps, it is recommended to have a PSU capable of providing total of 42 amps on the +12 volts to provide all the components in the system with +12 volt power. The GTX uses around 260 watts under load which is only 21-22 amps http://www.guru3d.com/articles_pages/geforce_gtx_580_review,7.html

Graphics card power distribution is
The PCIe slot gives 75 watts = 6.25amps
6 pin PCIe power connector 75 watts = 6.25 amps
8 pin PCIe power connector 150 watts = 12.5 amps

Okay thank you. =)
And the 850 should be able to handle 2 gtx 670s 4gb and a OC fx 6350?

Yes no problem!