@Srihari: In the meantime I have also tried booting Windows 8, than rebooting into liveusb (I still haven't installed Linux on the PC, not until I'm sure I can work around the troubles), rebooting to BIOS then booting to the liveUSB from there, but none of them solved the touchpad issue. I have tried Fedora 20 again, and the touchpad works there again, so I must have another issue, sorry for the offtopic messages in this case.
@Srihari: In the meantime I have also tried booting Windows 8, than rebooting into liveusb (I still haven't installed Linux on the PC, not until I'm sure I can work around the troubles), rebooting to BIOS then booting to the liveUSB from there, but none of them solved the touchpad issue. I have tried Fedora 20 again, and the touchpad works there again, so I must have another issue, sorry for the offtopic messages in this case.