According to your error, PCI slot 1 is the origin of this issue.
I would start by checking what device is installed on slot 1, and first just reseat it. If the issue continues then remove it and see if you still get the error. Depending on the card you could also try moving it to another slot, if one is available.
There is a diagram of the system board, showing where each slot is, on the link below.
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