how to update PCI express root complex. I think this cause my computer slowing

Hello, maylaneeza sapie

Welcome to Microsoft Community.

In theory,Updating the PCI Express Root Complex is not a typical or straightforward task, and it's unlikely to be the cause of your computer slowing down. The PCI Express Root Complex is an integral part of the motherboard, and its functionality is closely tied to the motherboard's chipset. In most cases, updating the root complex requires a BIOS or UEFI firmware update, and it's not something that users commonly do.

The update of BIOS/UEFI depends on your current motherboard manufacturer or OEM provider, if they can release an update, you can go to the official website of the motherboard to see if there is an applicable update package for your motherboard.

If you are experiencing slowdowns or performance issues with your computer, there are several other potential causes you should investigate first before attempting to update the PCI Express Root Complex, The following are some official tips from Microsoft for improving computer performance. You can try to execute them one by one and observe the results:

Tips to improve PC performance in Windows - Microsoft Support

If you still experience computer slowdown, you can try to share some details with me. About when these slowing performances occur, and whether they occur when specific programs are running.

Best regards,

Chandy |Microsoft Community Support Specialist