2010 unibody flashing question folder at startup won't disappear ???

[Chaznad]

So 2 weeks ago my hard drive went bad ( not recognized ). To confirm it was the HD , i borrowed an empty HD from a friend , installed it .. Got the question mark folder upon startup, put in the os snow leopard install disc , ? Folder dissapeared , HD was Recognised, formatted and i was able run the system to where everything worked perfect

Well I had to give my friend his HD back , bought a WD 500gb on ebay went to install the same way BUT this time, when the ? Folder showed at startup , I put the OS disc in and nothing would happen , it would just keep flashing .tried several times and still nothing

Any ideas what the issue might be , I'm kind of confused

 

[monkeybagel]

So 2 weeks ago my hard drive went bad ( not recognized ). To confirm it was the HD , i borrowed an empty HD from a friend , installed it .. Got the question mark folder upon startup, put in the os snow leopard install disc , ? Folder dissapeared , HD was Recognised, formatted and i was able run the system to where everything worked perfect

Well I had to give my friend his HD back , bought a WD 500gb on ebay went to install the same way BUT this time, when the ? Folder showed at startup , I put the OS disc in and nothing would happen , it would just keep flashing .tried several times and still nothing

Any ideas what the issue might be , I'm kind of confused

Can you force startup of the optical media by holding Option down during the Apple "bong" and seeing if you get a list of start-able volumes?

Do you hear the Superdrive spin the media during startup?