CPU affected my GPU temparatures?

So i have an MSI R9 380 and USED to have an I3-4160

When playing games my gpu and CPU temps were around about 62C and 60-65

I then got a I5- 4570 and my CPU ran colder (never above 60C) but my GPU temp then shot up to 67C from being around 62C and never above 65C. When playing games that is. I also have 2 top intake fans blowing directly onto my GPU.

Not exactly a big issue but i was just wondering what could have cause this to happen. Might it have been a bottleneck of some sort which didnt allow my GPU to run at it max potential?

Anyone have any ideas?

Could have not been fully utilized with the i3. Now that it's not bottlenecked it can work harder.

I think it is like you said

It could be that the GPU gets more work now.
More likely is that the CPU dumps out more heat. into your case. You mentioned top intakes. If you got an average case, that means the falling air stream takes heat from the CPU with it giving the GPU hotter air to start with.
Depending on your case, you could try to "redesign" your air flow. Maybe having top and bottom input and pushing out the top. The advantage would not be that big if there is any.

I might add, that I noticed increased CPU temps after swapping my 270X for a Fury.