I just read a review on the 470. It overclocks really well. Apparently so well that it can beat a 5870. Mind you, the 5870 isnt overclocked.
I just want a one card does all tbh. To get Physx I need to run three and they all end up running the same heat as a 470. Each card.
The 470 will easily match the 5770s in the worst case scenario and is one card. Has Physx, Cuda, and doesn't need patches profiles or anything else. I have begun to notice recently more and more games are only using one of my cards and it's mega hassle wiping all the profiles and putting them back ETC.
For the price I paid I'm dead chuffed. Only downside is Stepy has gotten his folding teeth in now and won't let go