I am looking for a software program that meets the following conditions: 1. Can thoroughly scan the blocks of a hard drive in order to detect corrupt blocks. 2. Can perform the operation described in 1 without the need for a second computer (because I don't have one). 3. Preferably a free program or very cheap if it exists. I just bought a new SSD and before I install Mountain Lion onto it I want to verify that the drive is good and does not have any corrupt blocks.