what are the benefits of having two graphic cards

[wakojako]

What are the benefits of having two graphic cards. Do you get double framerate?

 

[akshayghai29785]

almost 180%

 

[Paul Raver]

Scales up, not double numbers but still 2 moderate priced cards will outperform a expensive one in most cases.
And the cost would be similar or cheaper in some cases as well.
But what card you use to go SLI and what you want to compare them to etc.