Double Rail - combine 2 rails to get more amps?

[Majestic One]

I have an old Antec NEO480 [semi modular] and the 2 rails say +12V@18A, +12V@18A (though the manual says +12V@18A, +12V@15A).

my question is can i use 2 molex's from 2 different modular outputs (I have 4 total modular outputs) to get a combined amperage of 38A in this case?
I am looking to bolt it to a GF GTS250 1GB which comes with a double molex to 6pin cable and says, "Minimum 450W or greater system power supply (with a minimum 12V current rating of 24A)"

it is this card:
http://www.newegg.com/Product/Product.aspx?Item=N82E16814133389

but at the same time this card here has no mention of minimum PSU ratings, and also has a 6pin (clocks are a tad slower is all I see):
http://www.newegg.com/Product/Product.aspx?Item=N82E16814133392

Also is there any way to tell which of the modular outputs are the +12V one's or are the 2 rails divided between 4 modular outputs? There is nothing in the manual about this.
I am completely ignorant of how rails operate in relation to the modular outputs.

 

[rolli59]

When they say 24amps on the 12volt rail they are meaning combined and for the total system not just the GPU. Your PSU meets the minimum as is. Your plan to use two molex from two different cables is the correct way to hook up the adapter if you do not have the required PCIe connector.

 

[Majestic One]

cool, rolli.- thanks for that bit of info.

 

[delluser1]

It's old, it's inefficient, the combined 12v output was rated for 32a, it doesn't have the proper connectors and is peppered with Fuhjyyu caps.
I would consider myself lucky that it ran this long and put it to rest.