How to tell amps on a dual 12v rail psu

[kpelton94]

In my computer i have a 700w Raidmax RX-700AC Blackstone psu. im currently looking to upgrade the graphics. I was looking at a GTX570 which recommends a 38amp psu. my psu is a dual 12v rail design each with 23 amps. would i be able to run it. Do i combine the two rail amps to get the total amps. Thanks in advance.

 

[Emerald]

I think this should be right

[682W - (5V + 3.3V) * 25A] / 12V = 39.54A

 

[cmcghee358]

If each rail has 23 AMPS, make sure you use the 2 different PCI-E harnesses to plug into your card. ie not the daisy chain connectors, as they are obviously on the same rail.

 

[ko888]

Raidmax Blackstone RX-700AC

Total Output: 700W

-12V: 6W
+5VSB: 10W
Max Combined +3.3V & +5V: 150W

700W - 6W - 10W -150W = 534W

534W / 12V = 44.5 Amps

The Raidmax Blackstone RX-700AC's maximum combined +12 Volt current rating of 44.5 Amps should be enough to run a system with a single GeForce GTX 570 graphics card.

 

[cmcghee358]

Yeah but each 12V rail is limited to 23A, so it's important to use 2 separate rails for the Gfx card.

 

[kpelton94]

Best answer selected by kpelton94.

 

[Mousemonkey]

This topic has been closed by Mousemonkey