Judging from your specs - you may well get slowdown if you are running witht he details levels set high - especially at resolutions upwards of 800x600.
At 700mhz your processor is unfortunately fairly slow now...and things are not helped by you graphics card - a GF4 MX is really no better than a GF2 GTS......thats why I bought a GF4 Ti4200.
My advice is that you will have to lower your details levels slightly, and possibly drop a resolutioni too - on my 1.1Ghz machine with a GF4 Ti4200, Medal of honour can be slowish in places if I crank the resoultion and detail levels up to high...
Given that "entry level" specs now are 2gh+ with a Ti4200 this is not really too suprising.
Sorry to give you bad news, but it looks likes it might by upgrade time again........
