There is no such thing as an i3 4750K.
The only Haswell "K" CPUs are the i5 4670K, i5 4690K, i7 4770K and 4790K. "K" denotes an unlocked CPU, and there are no unlocked i3's except for the i3 7350K. Additionally, all i3's will have a "1" or "3" as the second number in the model number - e.g. i3 4160, i3 4330, i3 4370, i3 6100, i3 7300. None of them have 7's, which denotes an i7.