I didn't get answer to my question. Is it problem unclear or unknown? In installation process of Fedora Core 3 test 2 for AMD64 I got such bug message "Bug: Assertion (heads > 0) at disk_dos.c:471 in function probe_partition_for_geom() failed." (after keyboard configuration). If I press cancel I can go through other steps, but when I got the same message when it is time to copy packages to disk and installation stops.