PCIe usb cards causing trouble with 2019 MP

I have 3 Sonnet USB3 PCIe cards Installed in my new 2019. They were previously in my 2008 MP and worked like a dream providing 12 extra USB ports. Now after install the 2019 won't fully boot just stalling on a black Apple screen. I’ve been able to use the card in the very bottom slot but not the ones located in the upper slots. Trying to plug in a USB cable to these cards crashes the computer. Is it the way I have them installed? Asking the experts here.


Thank you!



[Edited by Moderator]

iPhone SE

Posted on Sep 17, 2025 3:14 PM

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PCIe usb cards causing trouble with 2019 MP

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