kwin takes 35% of CPU - how to tweak KDE faster?

[JuhaniJaakola]

I have Acer Aspire 7720ZG with Intel dual-core T2310 processor (1.46 GHz). According to top, kwin takes 35% of the processor. Are there any settings in KDE which would make it lighter?

[ozjd]

Try experimenting with disabling various effects. Blur is often a problem.

[JuhaniJaakola]

The problem has something to do with Firefox. If I have Firefox running with about 30 windows, kwin task 35% of the CPU. But if Firefox is not running, kwin takes only 5% of the CPU.

[ozjd]

Sorry can't help with Firefox, don't use it.