Do I need multiple cores?

ok, so i play DDO (Dungeons & Dragons online). it isnt a very demanding game, and i can play at almost max settings. my current specs are: athlon ii x2 270, radeon hd 6670, 4gb ram, 480 watt psu (it has plenty of amps on 12v rail) mobo is biostar a960D+. i have noticed that my cpu is bottlenecking my performance in the game cuz overclocking it increases my fps. my real question is when i upgrade my cpu, should i get a better dual core cpu, or quad core? i dont think DDO can use multiple cores, so shouldnt 2 cores be best, 1 for the game, 1 for windows?
 
Solution
and the 6300 + EVO i mentioned can be easily overclocked to match the single core performance of the 4350. it will be better for most games overall. Plus a lot of motherboards allow for cores/modules to be disabled. That is to say with a limited voltage supply to the CPU, you could turn off a module, and have the 6300 act as a 4300 essentially, allowing more juice to each cores (if you were really in a situation that demands that extra single core performance).

just some food for thought.
ok, so because i can almost play at max settings, i dont see a reason to buy a new intel mobo and cpu. all i know about my mobo right now is it is a a960D+ and i know it supports up to 95 watt, not too sure about 125 watt, but it says it supports fx series. ill have to look on the board tonight to find the revision number. so, it shouldnt really matter the amount of cores aslong as it has a better single core performance?
 
well, the phenom ii 965 BE is a little faster at single core tasks, and faster at pretty much everything else, and is unlocked. however, it is 125 watt which idk if it will work. i will progly go with something similar to this. the athlon x4 750k and 760k are even faster, cheaper, but are socket fm2, meaning i would have to buy a new mobo. anyways, depending on how much money i get, i will probly upgrade my cpu, or mobo and cpu. ty for your input :D
 
and the 6300 + EVO i mentioned can be easily overclocked to match the single core performance of the 4350. it will be better for most games overall. Plus a lot of motherboards allow for cores/modules to be disabled. That is to say with a limited voltage supply to the CPU, you could turn off a module, and have the 6300 act as a 4300 essentially, allowing more juice to each cores (if you were really in a situation that demands that extra single core performance).

just some food for thought.
 
Solution
hmmm yeah, i think going with an fx 43xx or 63xx would probly be the cheapest way to go, probly with the 6300 and OC it, but not much as my mobo is a cheap microatx board.ill see what temps i get with the stock cooler i have, if it is too high ill get the evo. thanks for your input! :D