If we're just talking about COD I think having the following is what gives you the best return on investment:
I really don't think having a supercomputer helps after you hit a pretty mediocre hardware peak, then it just comes down to the user and a combination of the above. If you have a reasonable amount of each of the above you'll probably perform better than someone with a £600 GPU but lacking big time in any other given category
- A net connection with the lowest ping possible
- A graphics card good enough to run at a constant smooth 60FPS for whatever resolution you're running
- A decent keyboard/mouse
- Map knowledge
- A decent headset sound setup
- High res monitor is a bonus
I really don't think having a supercomputer helps after you hit a pretty mediocre hardware peak, then it just comes down to the user and a combination of the above. If you have a reasonable amount of each of the above you'll probably perform better than someone with a £600 GPU but lacking big time in any other given category