Same issue, bad quad core optimisation. And gpu usage.

Pc specs:
CPU: i5 - 2500k OC @ 4.6Ghz
RAM: 8GB @ 1600mhz
SSD: 128GB game is installed on ssd
GPU: GTX 670 FTW

Hopefully at release it will be fixed to fully utilize Quad core + GPU usages.
Wish they would just confirm that its being worked at. AS 30fps is not fun to play at.