Hi there, For Adobe apps the i7 series is generally rather good.
This review shows Adobe premier performs better with the i7 950 than the AMD Phenom II 1090T Hex core, and
this comparison shows the i7 950 again beating the 1090T in photoshop retouch artists speed.
As for "firewire i/p", is that IP over 1394? If so, I don't know of any consumer graphics card with a firewire port, perhaps some of the professional graphics cards support it.
Here is the spec I came up with:
I included a CPU cooler so you could try overclocking - the 950 chip should hit 4GHz without too much trouble using that cooler. Alternatively, you could buy a
pre-overclocked 4GHz bundle from OCUK, and pay a premium.
If you feel that you would so well with 12GB of RAM, I suggest you go for
this RAM instead, it should still be within budget.
The graphics card (GTX 460) is one of the best bang-for-buck models available right now, it will play the new COD (and pretty much any other modern game) very well.
I also included a standard hard disk and a 60GB SSD. If you put your OS and main applications on this SSD then you will find the system boots up very quickly and everything feels "snappier" in use. The 1TB HDD is there for storing all the rest of the files - it is nowhere near as quick as the SSD, but for a mechanical hard disk it is one of the best.