Resident RPS hardwaresman Jamesstruggled with performance, too.
The Witcher 3s next-gen PC update is disappointingWatch on YouTube
Here’s the tweet.
We are aware of the issues PC players have been reporting since last night’s release of the update.

Thank you for your patience!
Here’s hoping CD Projekt addresses that, as well as the crashes and ray-tracing woes.
Hanging low-spec system owners out to dry would suck.

Probably best to hold out for those fixes, though.
Keep an eye ontheir Twitter.