Can O/C Damage HDD?

I just had to RMA a new HDD, but then it dawn on me, maybe it was because I did something wrong to the HDD.

I have my Q6600 to 350x9 mem 4:5.

No an OC can't damage a hard drive in any normal circumstance, but an unstable OC could corrupt data on the hard drive.

way back in the day, when PCI frequency was tied into FSB speed, overclocking the FSB also raised speeds of PCI devices, which could cause marginal equipment to fail.

Newer boards all (or have the ability to) lock the PCI bus to 33mhz. I highly doubt your overclock killed your HD, but if you're paranoid about it, go into the BIOS, and make sure the PCI bus is locked.

I have had IDE controllers fail due to overclocking while using a crappy PSU, but never lost SATA controllers or HDD's themselves.

Data corruption is very common if you push too hard. System32 files are usually the first to go