I quote from your review
"In 98% of today's games CPU cores wise whether you have 2, 3 or 4 CPU cores it will seriously not make a difference, as they will only utilize a maximum of two simultaneous cores. For that matter a faster dual-core processor will give you more performance than a slightly slower 3 or 4 core processor. Fear is rather GPU bound though. As you can see, virtually not a difference on any of the platforms."
HIlbert, I recently read an article where they took a 4870 X2 and benchmarked it with Quad, Dual Core Intel and AMD CPU's. ranging from 1.6Ghz underclocked to 3.6 Ghz overclocked.
In this it became apparent how big a difference a CPU can make, some games showed increases of 50 FPS @ 1920x1200.
I am telling you this because I wonder if you have the time to test this with your benchmark suite using the 4870X2 and the GTX 280.
This will show the difference a CPU makes when using Xrossfrire or SLI or a single card, you could possibly try and reach 4Ghz and see what impact it would have.
Thank you.