On 49.0.2711.0 build everything is fine! The problem resolved.

In browser was opened a large number of tabs in 3 different windows. This is about 50 tabs in total.

Well, I guess I don't open that many tabs.

I want to say that earlier the same number of tabs didn't affect on performance. Only on this build something happened. And I don't remember that the load on the CPU in them was kept permanently.

What OS? I can see a somewhat quick high CPU usage when loading pages but that's all and it doesn't seem to affect other programs or navigation.

Windows 10 x64 with latest updates. In browser was opened a large number of tabs in 3 different windows. This is about 50 tabs in total. Yes, when you opened one such quantity with lazy-option turned on, there was a load, but not such and not constant. The tabs keep a constant load at the level of 4-6%, which in the sum loads all the CPU cores by 100%. The load does not decrease with time and this affects of the OS performance: https://www.dropbox.com/s/irczjl6t9ps7n9g/IMG-20170907-WA0011.jpg?dl=0

P.S. Sorry for my English.

On this version CPU load on 100% in all cores!! 30 minutes - everything is still...