Samsung B75s1: Bios Exclusive
Many older Samsung OEM boards have "Secure Boot" or "Legacy" settings that prevent modern UEFI-only graphics cards (like the RTX series) from booting. A BIOS update often improves this compatibility.
For most Samsung B75S1-based desktops, you should visit the Samsung Support website and search for your specific model number (e.g., DB400S3A). Download the utility. Samsung B75s1 Bios
Ensure this is set to AHCI . If it’s set to IDE, your SSD performance will be significantly throttled. Many older Samsung OEM boards have "Secure Boot"