SLI vs. CrossFire, Part 1 – mid-range multi-GPU scaling & value
F.E.A.R.
F.E.A.R. – First Encounter Armed Assault – is a DX9c game by Monolith Productions that was originally released in October 2005 by Vivendi Universal Production. Later, there were two expansions with the latest, Perseus Mandate, released in 2007. Although the game engine is aging, it still has some of the most spectacular effects of any game. F.E.A.R. showcases a powerful particle system, complete with sparks and smoke for collisions as well as featuring bullet marks and other effects including “soft shadows”. This is highlighted by the built-in performance test, although it was never updated.
This performance test will tell you how F.E.A.R. will run, but both of its expansions are progressively more demanding on your PC graphics and will run slower than the demo. We always run at least two sets of tests with all in-game features at ‘maximum’. F.E.A.R. uses the Jupiter Extended Technology engine from Touchdown Entertainment. We test this game with the most demanding settings. We use fully maxed details with 4xAA/16xAF; soft shadows ‘off’, as they do not play well with AA.
Let’s start first at 2560×1600:
We see an interesting situation. Here the GTS 450 as a single GPU simply chokes at our highest settings. Adding a second GTS 450 in SLI allows it to easily play this game. We also see the minimums nearly triple when a second card is added for CrossFire. However, generally we see scaling of the average framerates is not great with SLI nor CrossFire in F.E.A.R. Let’s look at 1920×100:
The GTX 580 is the strongest video card in this DX9 game yet it is easily matched by GTX 460 SLI and beaten by GTX 460 SLI. We also see CrossFired HD 6870 and HD 5870 scale a little better than their GeForce counterparts. There is not much difference in practically playing F.E.A.R. between the fastest and the slowest video cards as the minimums are already sufficiently high.
I’m not 100% certain, but to analyze microstuttering, place a check in the box next to “Frametimes” in Fraps. Then when you press the hotkey, it will create a log file with a timestamp when each single frame was outputted. Only a few seconds is enough to make the log file really, really long. Then take a portion out of the log file and make a chart out of it, that measures the time between each timestamp, to see if the frames are consistent with each other in similar intervals, or if every other frame is too close to the other one.
If a game runs at say, 45fps with your SLI or CF setup, but feels more like 23-30fps, then definitely analyze this with FRAPS.
Great review so far.
How do the numbers change, if at all, if Split Frame Rendering is used instead of Alternate Frame Rendering?
The last time I used SLI was with my Voodoo2 3000s. It was a gigantic waste of $200, in 1996 dollars.
If SFR eliminates micro-stutter without too much of a performance penalty I might have to try SLI again.
why don’t they add BF:BC2?
and also 6950 n 6970 crossfire?
Concerning the microstutter, frames time (using that fraps option) is supposed to fluctuate more erratically on crossfire/sli than what it would be on a single card. I think instead of testing a moving scene, it would make more sense to test it on a completely still scene for a few seconds and see how they compare in the excel output file. You don’t want a moving scene because then you won’t be able to differentiate between the erracticness you would get from a moving scene and the erraticness you would get from microstutter.
Another interest option would be to downclock a sli/crossfire setup to a point where it matches the average framerate of the single card. This way you could could see if the multi-gpu setup looks choppier than a single card despite having the same average frame rate.
Excellent work! At the end, simple recommendations would have been nice. =)
Please include Civilization 5 if possible the next time you benchmark.
It is an important game which will test the tesselation feature and its scaling ability in multi-gpu configurations.
Civilization 5 has been added to my benching suite along with DiRT 3 and Total War, Shogun 2.
You’ve done a great job of benchmarking gaming performance, but including charts with FPS vs $$, and $$ vs wattage would be much more useful.
The wattage (both idle and load) figures can be especially important, as some of these cards can easily draw more juice than all but the most powerful (and expensive) power supplies can provide — and that definitely factors into the cost analysis.