Benefits Of Sli

[LucifersMagician]

hey guys i was juts wondering this SLI stuff...whats all the hype about really i dont understand...why have so much stuff if some games dont even use it?...me and Psychotic_God discussed it a little at school but i wanna hear some stuff from OCC

[Kamikaze_Badger]

First, a history lesson on SLI:

 

SLI, or Scalable Link Interface was first pioneered by... 3dfx... Back then, it was made for workstations by that company in an attempt to keep from going out of buisness. It was first used on dual GPU cards, as a way for both GPUs to be used. I believe it started with dual GPU VooDoo2s.

 

nVidia bought out 3dfx later on (long story behind that). They changed it from "Scan Line Interleave" to "Scalable Link Interface." The difference? Rendering methods. With the first SLI version, each card took turns rendering horizontal lines (according to Wikipedia).

 

Now, each card renders a certain percentage of a frame (for example:

framerender(char*,double);
framerender(card0, 70);
framerender(char* cardNumber[] , double frameSizeToRender) { ... }

And that's basic pseudo-code. The actual code is much more complex I believe.

 

Anyway, back to your original question: SLI usually gives you a slight boost in performance. HOWEVER, it does not "double" it, contrary to popular belief. nVidia has only stated that you will get up to 1.9x the rendering power with SLI. Also, SLI requires you to have a power supply beefy enough to handle both cards, along with the connectors, a motherboard with the nForce 4 chipset with SLI enabled, and two PCI-E x16 slots. You can expect maybe 1.3-1.5 your previous rendering power with SLI. Most of the difference will be in benchmarks, unless you want to run F.E.A.R. at max and get around 100 FPS.