i'm running two 7970s in dualfire, one uses two pci connectors 8-pin and 6-pin, and one uses a single pci-connector that has both 8-pin/6-in it. while i'm not having any issues, is it actuially safe to use a single pci-connector to draw power to both pins? if i could, i would rather switch to two connectors instead of the one, but because of the added chassis fan i installed blocks the bottom connections of my PSU, i'm forced to use the top connections, unless i get rid of the fan.
Can you please post a link to a picture or describe the connections in more detail? I'm having a hard time visualizing this.
It depends on how many watts that rail is rated to deliver. You can calculate this because watts = volts*amps. If you draw 225 watts max from those two connectors the rail with both connectors on it should be rated for above 19 amps.