I don't know if I understand this, but this is wrong! For example;
Originally Posted by hartz
You test KDE4 and XFCE on a Pentium 2 400mHz, 4MB RAM and an ATI 9200.
Conclusion: XFCE outperforms KDE4 because it requires less instructions to be executed, leaving room for a lot of other things.
Now let's re-run the test on a Core i7, 4GB RAM and an ATI 2400.
Conclusion: multiple cores so room enough left for other processes and due to KDE4's heavy cashing and whatnot it responds way faster than XFCE with a lot of things.