I just bought myself a new cpu, graka, MB, RAM, …
After I installed da hardware, I reformated my discs, reinstalled ET and I noticed now when I start da game, I see in console da following:
Hunk_Clear: reset the hunk ok
...detecting CPU, found logfile opened on Mon Jan 05 13:19:21 2004
Intel Pentium III
Bypassing CD checks
----- Client Initialization -----
----- Initializing Renderer ----
-------------------------------
----- Client Initialization Complete -----
Well, I got a pentium IV 2.8, not a pentium III. Any ideas on this?
Maybe this costs me some FPS 
