> I did a little research. On my machine with a 32bit system and off
> kdm_greet SAK is at rest, so I have not conducted further observations.
> Much more interesting results but I watched the 64-bit machine.
>
> 1. SAK is enabled: The CPU goes to 100%.
> 2. SAK is enabled: Switching NumLock on a PS/2 keyboard causes the death
> of the keyboard - everywhere - Xorg, console. USB keyboard switching
> NumLock survive fine.
> 3. SAK is enabled: If during the time between pressing the Ctrl + Alt +
> Delete and SAK display window, I press the Escape, SAK behave strangely.
> For example, dialog Desktop Session Locked remained displayed and next
> pressing Ctrl + Alt + Delete keys were ignored. And then kdesktop_lock
> goes to 100%.
> 4. SAK is disabled: Switching NumLock on a PS/2 keyboard survive fine.
> 5. SAK is disabled: CPU goes to 20% initially, but with increasing time of
> inactivity increases to 80%.

So I finally disabled SAK (when I tried it first time using kcontrol it 
doesn't seem work, but second time ok). So I can now use kdm to login 
again.

As Slavek described, there is still high cpu usage. On my laptop with 
Pentium M 1.7 MHz undeclocked to 800MHz its 50%.

Jansky