What is SLI and CROSSFIRE?

[ImNOOB00]

The question above says it all

 

[little_me]

typing that in google would have explained it.
SLI is Nvidia's means of combining more than 1 GPU together, while in theory, output performance should be +100%, it's more often closer to +30% to 60%
Crossfire is same, except it's for AMD.

You don't need to worry about it at all unless you plan on having more than one GPU of same type (yes, different types don't work well together) since most often, both will run at the speed of slower of the two.

 

[bignastyid]

Google is your friend. Even Bing can be helpful.