parvanov :
Can i overclock 3258 with a cheap h81(Gigabyte H81M-S2PV) motherboard and stock cooler ?
No.
If you read the article I linked they get minimal OC on an H81 motherboard and the stock cooler .
If you had a bigger budget and could include an H97 motherboard then the intel could be a good stepping stone , but if all you can afford is H81 you have made too big a compromise on the board to ever get the best from an i5
I suppose an alternate plan could be to buy a system with an i5 and an H97 board and use the onboard graphics till you can add a graphics card . But gaming would be pretty poor in the meantime .
If you do go the AMD way you you will have all the cpu performance you need for BF4 anyway
http://www.techspot.com/review/734-battlefield-4-benchmarks/page6.html
The FX4320 [ roughly the same as a 760K ] performs within a couple of fps of an intel i7 costing 4 times as much.
Again though these are solo player benchmarks . When you play online then more cores starts to pay off