Remove the drive from the PS3 then and depending on the make, download the corresponding factory tool (Seatools for Maxtor and Seagate, Data Lifeguard for Western Digital etc.) or a third party utility like Hiren's Boot CD, create bootable CD of it, connect the HDD to the PC, boot into the utility and perform Full Diagnostics, followed by a Zero-Fill. Repeat the process until you stop seeing changes in the Bad Sector count. If the drive fails to pass the test after 2-5 tries, it's on its last legs and will keel over soon. Good luck.