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My Macpro 4,1 does not show any of the Harddrives in the 4 bays, however when you look at the Sata/Sata Express in the system report (Serial-ATA Device Tree) Intel ICH10 AHCI. A work around I have removed the dvd drive and booted the system from one of the Sata connections (it works, for both the connectors). How do I check if the Harddrive bays are getting power from the main board? Any Help is greatly appreciated! Thank you in advance.
Most likely your power supply has failed. Keep in mind your PSU has a a few power legs. The drive power lines likely are dead. I would get a junker drive so you can take the connector off to wire it up so you can measure with a DVM the power feeds. Here’s the wiring diagram from the cable side:
Here, you’ll need the connector wired to plug into your drive backplane. 2009 - PSU - 661-5011 2010 - PSU - 661-5449
