In this link there are photos of the motherboards (and there are some more if you click in the other wiki pages dedicated specifically to every motherboard model)
https://www.psdevwiki.com/ps3/Motherboard_Revisions
As example, in JPT-001 the solder points of the SATA connector are located at bottom side, are that solder "blobs" aligned with the pins
The SATA pinout is standard, i found this link in google where is explained
https://e2e.ti.com/support/processors/f/791/t/552017
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But before that i would try to check the pins of the faulty hdd for curiosity sake, is mostly to see if the 5v pins are connected to gnd pins
In your last post you mentioned the PC was able to boot with the hdd connected so maybe is not this kind of shortcircuit, but dunno, just incase, is easy to check