I have i5 2500k and want to upgrade, what's the best I can get for lower $300s?
For that price you're going to do a sidegrade to a 3570K for a 2 to 5% gain at best at stock speeds and overall slightly worse OC potential.
And that's if we take into account you're not going to change the motherboard to upgrade to a newer socket.
Just don't.
>>54836435
get an i3-6100 for 100$
>>54836695
Or buy an cheap second hand i5 6500 - for 180 usd or less.
>>54836435
i7 3700k, it's the only upgrade that's really worth it. Getting another i5 would be a marginal upgrade, not worth $200 IMO.
>>54836435
sell your motherboard and cpu and add that to your $300 and boom you got money for whatever combo you want within reason