It’s unlikely to do much more than fry the USB controller. The thing is that most USB controllers are integrated into the southbridge chip on the motherboard and that controls most peripherals and the BIOS. Fry the southbridge and you render the motherboard largely useless. It’s highly unlikely that it would make its way through the southbridge to the northbridge across the PCI bus to a hard drive controller to a hard drive to fry it. There’s just too many tiny wires along the way that almost certainly fuse out.
Basically this is a mischief tool marketed as a “tester”.
