It's too bad you're too lazy to search. Laziness also can cause the problem you seem to have with having lack of cash.
why would you buy a sempron 3400
Dare I ask how much are you spending? What do you need, a full setup or something less than that?
Why would you buy the 8600GT? The 2600XT costs the same, but is faster. If you are that worried about price, you are better off buying the 7600GT for ~$90. Also, why buy the Sempron 3400+? Grab a slower chip and overclock the crap out of it.
Fear extraction point is more demanding than original FEAR and is fillrate/memory bandwidth hog. It won't run too well with and 8600gt nor 2600xt.
I was using a 1950pro and it wouldn't even let me play 1440x900 16xAF at max quality except soft shadows while I could with original FEAR @ 1440x900 2x AA 16xAF.
its a setup I have now and was just wondering about benchmarks i can overclock a sempron 3400 2.00 to 3.0ghz 5100 sempron but i need faster memory so it has some overclocking potential, mulitplier is locked at 10