I’m having a similar problem with my Gateway notebook, running 32-bit Vista. I have the same Optiarc CD/DVD RW AD-7530A ATA combo drive, It stopped reading DVD’s completely, but CD’s work fine… weird.
Drivers are up to date, drive is clean, tried uninstall/reinstall, deleting upper/lower filter, etc etc etc.
My warranty is (of course) expired, so Gateway wants big $$$ for support, and this forum is the closest I’ve come so far to ANY kind of real info for a 7530.
Any help provided earns everlasting indebtedness!