After upgrading from Kubuntu 13.04 to 13.10, I'm finding that my screensavers are consuming about 30% of my CPU even after they have stopped. I've noticed this specifically with KDE Asciiquarium and a couple of others. The "Blank Screen" screensaver seems to work so I've been using that as a workaround.
I found this bug below which seems related but I'm not sure if it's the exact issue.
Has anyone else experienced this and have a workaround?