10GbE cards like the ASUS XG-C100C are X4 so they probably won't work. Plus you'd have to cut the X1 slot.
I think the most you can get for X1 is 2.5GbE.
AMD Ryzen 5 3600 - 2019PGT
MSI X470 Gaming Plus Max - 22.214.171.124
ASUS GTX 1060 Strix 6GB
2x8GB G.Skill Trident Z 3600C15 @3800 14-15-12-28-40 1T 1.52V
Samsung 970 Evo Plus 250GB
2x Samsung 860 Evo 500GB
2x Crucial MX500 1TB
Super Flower Leadex II Gold 650W
be quiet! Dark Rock 4
Logitech G502 Proteus Core
Logitech G440 hardmat
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