CD Projekt Red have revealed the PC requirements for The Witcher 3 via Twitter
Minimum System Requirements:
Intel i5-2500K 3.3GHz or AMD Phenom II X4 940
GeForce GTX 660 or Radeon HD 7870
6GB RAM
OS 64-bit Win 7/Win 8(8.1)
DX11
HDD 40 GB
Recommended System Requirements:
Intel i7-3770 3.4 GHz or AMD FX-8350 4 GHz
GeForce GTX 770 or Radeon R9 290
8GB RAM
OS 64-bit Win 7/Win 8 (8.1)
DX11
HDD 40 GB
CD Projekt Red’s twitter https://twitter.com/witchergame