The SLI efficiency is lower in this game at 80%.
It’s a good result nonetheless. The low bottom speed of the SLI tandem has nothing to do with the SLI technology because the single-processor cards have the same problem.
Metro: Last Light
With Advanced PhysX turned on:
And with Advanced PhysX turned off:
In both cases the standings are the same. The SLI technology is expectedly more efficient at high loads (i.e. with enabled Advanced PhysX). The GeForce GTX 690 is always a little slower than the two GeForce GTX 770s.
GRID 2 is the only game on our list where the 2-way SLI tandem built out of GeForce GTX 770s is not very efficient. It is only 15 to 31% faster than the single GTX 770. The dual-processor GeForce GTX 690 isn’t any better. Hopefully, driver updates may bring some improvements in the future.
Company of Heroes 2
Although newer than GRID 2, Company of Heroes 2 responds well to our enabling SLI mode at 2560x1440 pixels with antialiasing. The performance boost is 75-81% then, but no higher than 50% at the lower settings.
Here’s a table with full test results, so we can move on to our summary diagrams.