My pc keep restarting when installing

[stlony]

hello,
i have a problem when installing universal mac os x 10.6 on my pc after the startup menu the pc is restarted even if i typed -v it reatch to start darwin kernal then restart it never get to the diagnostic screen any idea ??
my pc is msi 915 MB processor 3.00 GHz nvidia 7300 2 giga ram