Years back I tested the game out on my 4 core CPU. I set the affinity to only use 1 CPU, then 2, then 3 and finally all 4.

Here are the system specs to the best of my memory:

• CPU - Phenom II x4 940 @ 3.6GHz
• GPU - dual 8800 GTS 512MB in SLI (the ass kicking G92 chip, not the crappy 320/640MB G80 cards)
• RAM - 4GB DDR2 800
• HDD - 500GB 7200 WD Black Caviar
• OS - Windows XP 32bit

I wish I could find the information I copied down when I did this testing, sadly I can't find it and I don't remember where I posted my findings. What I can tell you is that the game (original) did utilize multiple CPUs, although it wasn't that well optimized for multiple cores.

I set the affinity for the game to utilize different amount of cores, then I'd play through an action heavy area with each setup. Affinity lists the CPU cores as Core 0, 1, 2 and 3.

Going off memory (12+ years now), here's what I recall.

Using 1 core, I want to say I averaged around 32fps. CPU Core 0 was constantly spiked 95%+ while gaming

You did get a bump in performance with 2 cores to run the game off of. Going from a single core to a dual core gained about a 30% improvement on my system. Let's say I was getting around 32fps on average with 1 core, I was getting around 41fps with 2 cores. Core 0 was usually around 70% and Core 1 was usually around 40% usage while gaming.

Going from 2 cores to 3 cores I noticed a minimal amount of an improvement - going from around 41fps to 43fps, which is about a 5% increase. Core 0 was around that 70% usage, Core 1 was around 30% and Core 2 was around 15% usage while gaming.

Going from 3 to 4 cores I noticed no change in the fps. Core 0 stayed around 70% usage, Core 1 was around 30% while Cores 2 and 3 both were around 10-15% usage while gaming.

I can't say for sure that Core 3 (fourth core on the CPU) was being utilized by Crysis. I saw no difference in fps counts going from 3 cores to 4 cores. I can only speculate and draw these possible conclusions.

1. Core 3 did very little work with Crysis that the usage of it is negligible.
2. Core 3 did very little work with Crysis and some of the activity I noticed on it was also from the OS doing background processes.
3. Core 3 did no work with Crysis and the activity I saw on it was the core simply handling background processes from the OS.

The multitasking of CPUs was there with Crysis, but any CPU with more than 2 cores really didn't benefit much; at least based on my testing.