How bad is a CPU 'bottleneck'?

[The Seventh One]

Hey all, I got the XFX 4890 recently and before I bought it I was aware of bottlenecks but couldn't really tell by how much. Been playing COD4 and in some places... fairly often in fact, my FPS drops to like 20, I didn't expect the bottle neck to be quite this severe.

I am playing with everything on max and at 1680 x 1050 to try put more stress on the card instead. My specs are as follows:

DFI LANPARTY UT SLI-D
AMD 4200+ X2 overclocked at 2.75GHz (Stock is 2.2GHz)
2 gig of RAM
XP SP2 (Fresh install just today), I also have access to Vista and Win7
Catalyst 9.5

It's an old rig I know but I had the 4890 as a bit of 'later on in the year proof' as thats when I plan on updating the rest of my system.

So in conclusion, is the bottleneck really that bad? and is there anything I can perhaps do to improve on the FPS with the current setup?

Thank you in advance

 

[The Seventh One]

Yet again thanks a lot for the very swift replies and advice. I'll just have to wait it out until I can afford the rest. The whole reason I started with the gfx is because I had a 6600GT so even though there is a bottleneck, the 4890 is still a huge improvement starting point nonetheless

it's ram more than cpu i would say. with a 4890 with 1gb of gfx ram and 2gb in your system already you will need to upgrade your OS to a 64bit version to use more ram

Going to try this today, got nothing to lose