Version: (using KDE 4.3.2) OS: Linux Installed from: Mandriva RPMs In my konsole profiles, I use the font "Terminus", which is a bitmap font. I noticed that if I uncheck the "anti-aliasing" checkbox in the profile configuration dialog, konsole refresh becomes very slow, when scrolling the window, or minimizing and restoring it: one or two second to refresh one page of a full screen konsole. If I keep the "anti-aliasing" checkbox checked, speed is normal. I have a NVidia card and use their driver in version 190.42.
This is apparently a NVidia driver problem. I use now the Nouveau driver, and I don't have that problem (I have others, but this is another story...)
Same problem here on openSUSE 11.2 for x86_64 and an ATI video card after upgrade to KDE 4.4.1 from KDE 4.3.5. Konsole from KDE 4.3.5 had no problems with or without aliasing. KOnsole from KDE 4.4.1 is painfully slow. $ rpm -q konsole konsole-4.4.1-154.4.x86_64