gabriel.vikstrom :
I got a ASUS H81 Gamer motherboard. I just read somewhere that almost every 1150 motherboard can overclock, is that true?
Yes, the H81 will be able to overclock. But remember, this board was not designed to be overclocked and it does not have adequate power delivery or VRMs to get much of an overclock. So don't expect a heavy overclock on this board.
My suggestion is the keep the board and get a i7 4790. It is still one of the better CPUs for gaming even though it is a few years old. I would think the 4790 will be adequate for the next 1 to 2 years.
I am not sure how much RAM you currently have. 8gb is the minimum for gaming these days. So if you have less than 8gb, then you need 4gb more. RAM can be very finicky. Mixing and matching RAM does not always work, even if it is the same model. This is why RAM is sold in kits as they are tested to work together. You also have a dual channel board. Most modern mobos are dual channel. That means you need RAM in pairs of 2. So if you have 8gb installed on your PC in 2x4gb sticks, adding an additionally 4gb stick may give you some problems. So you should look at a 2x4gb kit for the upgrade.
Like I said, mixing and matching does not always work, but most of the time it does. So just buy a kit from a vendor that accepts returns just in case it does not.