How do dual Video cards work? AMD and Nvidia?

I have 2 questions here, maybe. The first is my main question. I build my own computers because I enjoy it, and I use them for gaming and entertainment. Here is my question - How do dual video Cards work? Right now, I have a 6770 for my gaming computer, and I plan around summer 2012 to build another computer. I am now wondering, how do dual video cards work? I mean, is it as simple as buying 2 Cards, and as long as the Mobo has all the specs and you have enough power, will it work? I understand some configuration must be done, but I do not know anything. Some videos would help greatly. My 2nd question is simply, Does linking 2 Nvidia cards differ from linking 2 AMD cards? Thanks!|||before you link 2 gfx cards together make sure you have the power to push it (powersupply)

they need to be connected via a bridge.



nvidia and amd uses different technology. amd is crossfire and nvidia is SLI



for more info on Crossfire go here

http://en.wikipedia.org/wiki/AMD_CrossFireX



for more info on SLI go here

http://en.wikipedia.org/wiki/Scalable_Link_Interface



make sure when buying the cards, buy the same manufacturer and same models. so less problems will arise.



note some mobos may not support amd's crossfire or nvidia's sli

so choose carefully.