Looking for graphics card and psu compatability assistance.

[Dooflop]

So basically, in a nutshell the problem im facing is replacing a friends video card. His current psu is http://www.newegg.com/Product/Product.aspx?Item=N82E16817103942

I was looking for graphics card upgrades, i noticed his PSU has 3 12v rails@ 16a each with a max load of 32 amps across all rails. However when looking up the amperage specifications for his previous video card, i noticed the minimum requirements according to this : http://forum-en.msi.com/faq/article/printer/power-requirements-for-graphics-cards

My friend was running a 9600 gt which according to the above link demands 26a minimum with a 450w PSU. Is this just incorrect information? or why was my friends pc able to run with a 26a video card using a 16a single rail?

All help is appreciated.

 

[completelyrandomname]

That should be a good PSU. You should be able to get a GTX 650 Ti, 7790, or a 7770 no problem. For the multi rail power supply you can't just add the 12v's, it doesn't work that way. You don't need to be too concerned about it though.
EDIT: You should be able to get a 650 Ti Boost going also. Get any of these and you're off to the races:
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007709%20600315498%20600423185&IsNodeId=1&name=GeForce%20GTX%20650%20Ti%20BOOST
If you can't afford those then get a 7790:
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007709%20600286767%20600423073&IsNodeId=1&name=Radeon%20HD%207790

 

[Dooflop]

That should be a good PSU. You should be able to get a GTX 650 Ti, 7790, or a 7770 no problem. For the multi rail power supply you can't just add the 12v's, it doesn't work that way. You don't need to be too concerned about it though.
EDIT: You should be able to get a 650 Ti Boost going also. Get any of these and you're off to the races:
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007709%20600315498%20600423185&IsNodeId=1&name=GeForce%20GTX%20650%20Ti%20BOOST
If you can't afford those then get a 7790:
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007709%20600286767%20600423073&IsNodeId=1&name=Radeon%20HD%207790

Could you explain to me how his multi-rail psu with 16a per 12v rail is able to run a 26 amp video card with a single pci-e plug? Doesn't that mean its pulling one 12v rail? which maxes at 16a? Is it being supplied more amps from the excess not being used on the motherboard rail through the pci-e slot?

 

[completelyrandomname]

Read this: http://www.overclock.net/t/761202/single-rail-vs-multi-rail-explained
and this:
http://www.tomshardware.com/forum/306437-28-single-rail-multiple-rails-eternal-question-answered

 

[Dooflop]

According to the psu specifications its max load is 32a across all 12v rails. So correct me if im wrong, I read those posts you linked. "the true current limits are usually set 3-5A(36-60W) higher than the label shows" is a statement from the post. So then does that mean it can use multiple rails for one pci-e plug? up to a maximum load of 35-37ish amps? and that would be considering mobo and cpu amps aswell correct? sorry if im asking alot of questions, im just an IT tech in training and id like to come to a complete understanding over this. I appreciate the responses i have gotten from you so far.

 

[completelyrandomname]

I'll admit, I never researched a lot into multi rails. But the part about a PCIe plug using multiple rails is correct. (at least I think so, I could be wrong)
Here is how you calculate your PSUs 12v: http://www.overclock.net/t/131388/how-to-calculate-the-max-amperage-on-psus-with-multiple-12v-rails
Apparently you have 38a of total power. Therefore this is how the graphics card was able to work. If you are considering an upgrade, like I said the 650 Ti Boost and the 7790 are great options.