This is where OSx86 can get a little messy. I haven't had any luck with getting an IDE DVD drive to work at all either with installing on a 531. The fact that there are no IDE ports on the MB and that PCI-IDE adapters haven't been made to work yet, really creates a hard place for this OS installation. The only thing I can suggest is buying a cheap SATA DVD ROM or RW. In the end, it will work with all your other Operating Systems. Keep the external DVD RW so you can write while in OS X. The kernel extensions made for your NForce chipset don't allow writing with SATA DVD RWs.

Hope this information helps.

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