Hi @Richard_z,
Thank you for posting in Intel Ethernet Communities.
1) Please share the PBA of the adapter. You may refer to the link below on where to find the PBA number. Providing photos of the adapter focusing on the markings (white sticker) found on the physical card will be highly appreciated for us to double check on it. The PBA consists 6-3 digit number located at the last part of the serial number. This would help us identify if you are using an Original Equipment Manufacturer(OEM) or retail version of Intel Ethernet Adapter.
Identify Your Intel® Network Adapter Model Using PBA Number
https://www.intel.com/content/www/us/en/support/articles/000007022/network-and-i-o/ethernet-products.html
2) What is the model of your computer/system/board?
3) What is the operating system (OS) in your system and build version?
4) May I know the command you used to train/linking disable and enable at PEX8748 downstream?
As PEX8748 is one of Broadcom PCI Express Switches, may I know if you have reach out their technical support in regards of the configuration?
Looking forward to hearing from you.
Best regards,
BY_Intel
Intel Customer Support
