Hello! Why is there no driver for gigabyte rx 550 for OS windows 8.1 on the site?
Because Win8.1 is not supported for that card. Never has been, and never advertised as supporting any OS other than Win7 or Win10. Radeon™ RX 550 | High Performance Graphics Card | AMD
AMD Halts Support for Windows 8.1 with Consumer Radeon drivers
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