I'm not sure with that, but I think I remember at a time, I could scroll text without smooth animation. Now if I keep scrolling text over and over my cpu just burn.

Is there a way to de activate it in mirc or is there some windows setting ?

I think this is a windows setting.

View this page:

http://www.microsoft.com/windowsxp/using/accessibility/smoothscrolling.mspx

-genius_at_work

It doesn't work
I tried SmoothScroll reg setting, doesn't either work.
http://www.google.com/search?q=windows+disable+smooth+scroll

I tried the link on microsoft website, the registry setting, tried restarting mIRC, nothings changes, ans still my explorer windows just scroll not smooth.

Nobody has any suggestion ?