problem in installing mac(urgent help needed)….

whenever i install mac on my intel pc..i am not able to detect my hard-disk(tha mac disk i am using was already pre-patched)can anyone plz tell where i am doing wrong….urgent help needed…
Answer #1
Had similar problem with my apple comp, had to make new partitions during instaling mac os, you can do it at same screen when your HDD should be detected. There was menu on top I think. Otherwise I don’t know
Answer #2
but i am not able to detect my hdd……