6300 is his CPU, it should work. (6300 FX)
is your OS 64 bit? Because it is stated clearly upon installation of the Beta that PC beta will only be 64 bit.
Lag in FPS titles are caused by 2 things: Low specs (your fault), slow internet (can be 1 of two things, either your ISP & internet provider are slow/ the package you are using is a slow connection >1Mbps)
As a rule of thumb 1Mbps is the slowest you will want for fps gaming
Or your location is very far and the server you are playing on is located on the other side of the world. Thus there will naturally be a time delay as the data needs to transfer. You can see both of these if you hold Tab in and check your latency/ ping compared to other players.
If for example they are all between 10-50 and you ping is 200-300 then your internet is the cause. If not then it's your specs.
Unfortunately the power is out at my house today so I can't install the beta while at work as intended so I cannot give any tips inside the game
Lastly make absolutely sure your drivers are up to date.
The BF4 beta is an older version than what DICE are working on for the release, however it shouldn't lag for the general public. Unless EA has a new policy (I'm referring to Simcity
).
Hope you sort it out, please let me know which of the above mentioned possibilities it was so that I may further assist you.