Will gtx 570 will need to be sli"d to get better performance


You have asked that question several times and it has been answered several times, so stop making new threads asking the same questions.
 

Maybe, maybe not. Some cards go out of production quicker than others and in two years time you may only be able to get a second hand card from Ebay or similar.
 
OP:

good lord.... just get a single gtx 570 and see how you like it( I have one and it runs most physx games like batman aa and mirrors edge are the ones that I have they run on high at 1080p with medium-high physX settings) then if its not up to par then sli it, make sure to beg your parents for money at least 2 months in advance for this purchase... thread over