ide AND POWER CABLE REMOVED PC DOES NOT BOOT

[lostandfound+2]

well i replaced the cables of the master and the slave and rbooted the comp the computer goes into windows but in the bios it still shows pata master as dvd and pata slave as hdd.there is no option there to change it manually(in the drive config screen in bios).so i disconnected the ide of the dvd rom and went into bios and there it showed the pata master and slave both not detected.well my friend says here i should reset bios to default so the bios will now take the hdd as the master and not detect the slave.should i do this ? even if i do it how will i change it again when i reconnect the dvd drive as u cant change the settings of master and slave in the drive config option inthe BIOS.