Dear All,
I would ask your advice about a little project I have in mind.
I often use a SATA/IDE to USB interface to copy data from old hard disk to new PCs. This interface comes with a black brick with 12v-5v molex connector. For three times this external power supply has failed (once blowing the hard disk it was connected to

). I don't want to buy another one to get another piece of junk.
As I have a spare notebook power supply (19V - 4.7A output) I think it could give enough power to feed a pair of step down DC-DC converter (two of these:
https://www.amazon.com/dp/B008BHAOQO)
I can connect the two in parallel to the output jack of the Notebook PSU and feed a molex female connector, stripped from and old PC PSU, setting the outputs to 12v and 5v.
I think that the hard disk(s) will draw 1.5A max from both the power lines. Some hard disk have a 2.5A peak in the 12V line. I will connect only one hard disk at a time, and I would like to have a power source that would not blow up any hard disk I connect to it.
What do you think about this solution? Will it work? Would you suggest another solution? Do you think I need heat dissipation for the power regulators?
Thanks in advance.
Best regards.
Lorenzo