2. Yes. Look under "Features" in the spec list. "1 x 8-pin (6+2) and 1 x 6-pin PCI-E connectors" = 2 PCI power connectors.
The Antec 500 has 36 amps available on the 12 volt rails. An Oc'd CPU and the 560TI would use a max of about 25 amps leaving a comfortable margin for the rest of the system. I estimate that the PSU would be running at a max of 70% of capacity with a 560Ti.