which cpu from amd should i get

which cpu should i get when im ready to buy a quad core or dual i have narrowed it down dual core AMD Athlon 64 X2 6000+ Windsor 3.0GHz, AMD Athlon X2 5400B 2.8GHz and quad core AMD Phenom 9850 BLACK EDITION 2.5GHz , AMD Phenom 9650 2.3GHz all have to be able to run on 550w psu with hd4850 512mb also need to play crysis on high with no lag.

first of all,there are those who say that at this moment there is no real need for a quad core as far as general computing is concerned,,if on the other hand you are engaged in the kind of usage that requires multi cores video editing ,for example...
dual cores,,take for example the AMD 5000be,it's native ghz is 2.4 and can easily go higher,then there is the AMD 6400be @3.2ghz which except for the 1m onboard cache,is the same as the 5000be,and costs almost 2x the 5000be..
so what it boils down to is what you are going to do with your system,how much you want to spend,how long your selections will last,,and what kind of upgrade path will your selections offer you as time goes by..
and as for playing crysis on high with no lag,well that is your choice,methinks that there are better games out and coming in terms of storyline and player involvement,,although if you can run crysis at high settings with no problems........

get the 5000+ BE. all you have to do to get it up to 3.0 is change the multiplier...no need for voltage increase at all... also it only costs like $69.99 how could it hurt?