How can I tell which 12volt rail is being used?

See the table at the bottom of this page:
http://www.jonnyguru.com/modules.php?name=NDReviews&op=...

The short answer would be that each pair of 6+2 and 6-pin cables are on their own rail... so one hardwired 6+2-pin and one modular 6-pin per rail.

How do you tell the two hardwired cables apart? I can't imagine unless they are labeled.

I am reading up on it at the moment. Will respond in a bit.

@Proximon and hunter315,

wow thanks guys for the link, that review was pretty easy to follow and digest. I loved how the 12volt rails were labeled. Reason why i asked this question was that I got another evga 9800 gtx+ and wasn't sure if I was getting enough amps on them. There was no way to tell for me if they are getting their own 12volt rail @25 amps.

The power requirements listed for the card are always for the system as a whole, a 9800GTX+ only uses about 150W under full load or about 12.5A, each rail could provide enough power to handle 2 of them, you have plenty of power available to you, thats one of the upsides to a good power supply.

Another question comes to mind....since we're in the amps and watts topic....My question is my 9800gtx+ System Requirements on newegg says:

Minimum of a 450 Watt power supply.
(Minimum recommended power supply with +12 Volt current rating of 24 Amp Amps.)
Minimum 550 Watt for SLI mode system.
(Minimum recommended power supply with +12 Volt current rating of 30 Amp Amps.)

but is it talking about the total amps of the psu on +12 volt? or is it talking about 25amps on one rail?

I read in some review or forum that 9800gtx+ at max load eats 180something watts so; 180watts divided by 12volt = 15amps .....so basically it only eats 15amps @max load and my psu 12v1, 12v2, 12v3, 12v4 are all supplied with 25 amps per rail. Did that make sense? °_·

lol you answered my question even before i asked it. Well thanks alot for the help. It's such a relief knowing everything is stable now that i got my 2nd graphics card installed.

Its a pretty common question so i figured you had it too. Since the GPU pulls 75W from the slot(6.25A) which is powered by the 24 pin main, and a 6 pin provides 75W and an 8 pin provides 150W(12.5A), so in your case half the cards power comes from 12V1 and the other half comes from 12V3 or 12V4

Stupid question, what is a rail? Is it just a wire coming from PSU? Thanks.

Best answer selected by monkey_d.

Have a look at the PSU guide linked in my sig. In that you will find a link to a glossary.