Build Advice Would i see a big increase from this upgrade?

Current

CPU AMD A8-3850
Mobo F1A75-V PRO
2048MB ATI AMD Radeon R9 270

to

Gigabyte Z97X-SLI
Devils Canyon Core i5 4690K
XFX Radeon R9 390 "DD Black Edition" 8192MB

Would i be able to get away with just upgrading the GPU?

 

For pure gaming at regular 1080p a GPU upgrade would go a long way by itself.

If your talking more generally using non-gaming programs then the i5 4690K is superior in every respect.

 

It always comes back to the question "what is your PC currently not able to do that you would like it to?"

 

If i bought this GPU would i be able to run games on ultra with this cpu?

 

Depends at what resolution...

TBH, why don't you just buy the graphics card - then if you can't play everything on ultra, buy the rest of it too.

 

why didn't i think of that? wait! don't answer that!

/runs off