Tekla 21.1 System Requirements -

: Tekla rendering can use DirectX or OpenGL . Prioritize modern cards (like NVIDIA GeForce) that are optimized for DirectX performance.

The Tekla installer usually handles these, but ensure your system is compatible with these redistributable packages: Tekla User Assistance Microsoft .NET Framework 4.7.2 (or newer). Microsoft Visual C++ 2010, 2013, and 2015 Redistributables (both x86 and x64). Tekla User Assistance Display & Peripherals : A resolution of 1920 x 1080 tekla 21.1 system requirements