My Video card only came with 2 6 pin connectors from the PSU that are already being used to power the current 560 ti and I am wanting to put in a additional 560 ti in to run in SLI. Could I use 2x single or double 6 pin to 4 pin molexes to power the 2nd card so I dont have to buy a new power supply? The power supply is 850 watts. If so should I buy single or double cables 6pin to 4pin? Will this supply enough power? Will it burn my apartment down? Any advice would be helpful!!! Thanks.