tried everything, but no luck. Even the live-CD version does reboot spontaneously after selecting a (random) language and one of the install options. Resetting BIOS settings (of trying different BIOS settings) did not help. Changing the IDE channels (CDROM and HD on the same channel, different channel, etc) did not change anything. There is just no way to get Pardus running on the pc. Very frustrating indeed.
At last I took the Xubuntu CD and installed it within 10 minutes and without any problem at all. It's a pity, it would have been nice to use a distribution like Pardus, but it just does not run on my hardware.