I assume that you are trying to install iAtkos 7? With 10.5.7? I took a look at the HCL on osx86project and your HP isn't listed - http: //wiki.osx86project.org/wiki/index.php/HCL_10.5.7/Desktops (delete the space after : ). Also if you look, the recommended graphics is an X1300 or greater so that could also be a problem. You said you installed on a Pentium 4 with no problems - Was this a different computer? What were the specs of that machine?