Hello, I started playing The Witcher 2 but I get stable 18 FPS. No matter what setting I try the fps is very low.
My PC:
Windows 7 Ultiumate 64x
Intel Core i5-4460
16GB RAM
R9 290 4GB
Any ideas why the fps is so low?

Is Ubersampling off? Could you send a screenshot of the launcher options?

What resolution are you running the game at?

Does your system have a secondary GPU(e.g. an internal Intel HD Graphics), and is the game possibly running on it instead?

Judging by the performance (googled for R9 290, around there with Geforce GTX 970)), it should have enough power to run the game faster, unless you are trying to run it on some 4K resolution or such. Then again I don't have recent experience with ATI/AMD CPUs so no idea if they have some known performance issues with certain games...

UberSampling could be a reason. It really sinks the framerate, even on a 1070.

I'm running the game at 1920x1080. It mekes no difference when I enable/disable ubersampling.
FIXED I edited the file User.ini and set "TextureMemoryBudget" to 2048. Then I restarted my PC and now it runs smooth with almost stable 60fps.

Good to hear. Have fun!