What part to upgrade?

[OTWarrior via HWKB.com]

I have a intel pentium D 2.80ghz dual core processor, a sound blaster x-fi
fatality xtreme gamer, an ATI Radeon 1900 XTX, and 4 GBs of Ram, running
windows 64 bit.

I am starting to struggle with modern games, and was wondering which
component is the weakest, so i can upgrade it. I am guessing it is the
processor, however I was wondering what anyone else thought.

PS: does the motherboard make a dramatic difference?

NB: I also run games at 1920 x 1200 resolution.

 

[DaveW]

Running at that high of a resolution on your monitor, both your CPU and your
video card are holding you back. That level of resolution setting requires
a VERY powerful video card to play modern graphics intensive games.

 

[OTWarrior via HWKB.com]

Running at that high of a resolution on your monitor, both your CPU and your
video card are holding you back. That level of resolution setting requires
a VERY powerful video card to play modern graphics intensive games.

Would installing a second x1900 xtx in a crossfire setup give me the power i
would need? as I have heard using crossfire will improve performance by 50%.
Of course, I would have to improve the processor and motherboard due to
bottlenecking, and physical capacity on the motherboard/case.

which cpu and video card would you recommmend? (I am willing to spend up to
£400 on each) and which motherboard to get them to work together?

 

[OTWarrior via HWKB.com]

I have just seen some comparisons on tom's hardware, and from what i can see
my processor is the lowest powered component of my setup, and my video card
is not far from the best. So I only need to upgrade my processor and maybe my
motherboard.