I have two macbooks , both mid 2009. One of them needs a wipe and reinstall. However I have put the OSX disc and the applications disc in a safe place..ir I can't find them! I have the discs for the other macbook. As far as I can recall they are the same. The only difference is the macbook that needs wiping has a bigger memory and I think slightly faster processor. Can I use the discs that belong to my other mac or will it fail? Thanks!