Just a short repport. After a Mather-board change (bad circumstance), keeping the AMD FX processor and RAM, but passing from Oss-13.2 to Leap-42.1, I mentioned a big change in the behavior of the "same" kde3. In my default session, there was opening a window KSysGuard. I first thought that the motherboard was involved. After investigation, I finally noticed it was ksysguard himself, who was asking a lot of "power" to the cores. The chart attached, using GKrellM, reveals this problem : the big visible change in the last quarter of grafics processors is due to the closing of the window ksysguard !
An other great thank you for the KDE3 maintainer(s).