# of 12v Rails? Amps?

You will see on the power supply specs what combined amps it can output. All that really matters though is that you get a good quality unit from Antec, Corsair, SeaSonic etc. The multi rail design is supposed to give a more balanced power distribution and a more stable system at least that is the theory behind it, but like I said it matters more that you get a quality unit with the specified wattage.

For the 560 TI al you need is a good quality 500 watt unit I my self would go a bit higher like a 650 watt unit.

dual or more rails is fine. If you want 2 560 ti's you really should look at a 700w psu. Forget rails and amps, just look at quality units from Antec, seasonic, corsair, silverstone and OCZ are rating up there these days also. Read some articles reviews from hardwaresecrets and johnny guru to give yourself a bit more knowledge about psu's

Will this Antec work with 2 of 'em in SLI?

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Was also wondering about the MSI GTX 560 Ti and how it looks like each card needs two 6-pin powers. If I run two cards, will I need four 6-pin power connectors? Is there such a PSU or will the one above work?

Yes that particular PSU has 4 PCI-e connectors, and 62 amps on the 12v rails.    

That is the exact power supply I use it will be perfect to run two 560 ti's in SLI. The Hybrid cabling makes sense since you need the 24 pin, PCIE, and a few SATA power connections anyway the rest are modular.

Best answer selected by joshua07.