I bought this to try and dig some data off old computers & hard drives that I could no longer access. It turns out, out of three "dead" devices, I was able to recover data off two of the hard drives. A third hard drive would not power up even with the adapter.So, this won't help you if your drive is broken. But if it's a matter of just getting access to a hard drive that you otherwise can't connect to- broken laptop, bad power supply, bad USB/Firewire connections- then this product is well worth the investment.