Buy new GPU or buy whole new PC for VR?

[Smiley Crack]

Pretty straight forward, my PC is decent but the GPU lacks some power which is why I am planning on upgrading. Anyways, here are my current specs:
CPU: i5-3570k
GPU: GTX 760 (4gb ed)
MOBO: Asrock z77 extreme 4
PSU: Corsair TX 750 bronze
RAM: 12 gigs of ripjaws (forgot model)

I am planning on upgrading my GPU and getting a Vive (I did the test on steam and all it says is that my GPU isn't great enough). Therefore I want to upgrade my GPU to a GTX 980 TI EVGA.

Do you guys think I should get a new GPU or just go all out with newer and better parts?

 

[Forever Oleg]

Just get the GPU.

Even better, wait until summer and get the new Pascal GPU since 980 Ti will be replaced with it.