Preview settings don't affect your render- Vegas has to render the frames anyway and it just shows them to you.

In Voukoder x.264 and x.265 are always software (CPU)-based encoding. (Decoding= playback)
In Vegas, MagixAVC (Mainconcept) is software. MagicAVC or MagixHEVC with NVENC, VCE or QSV are hardware-based encoding.

Here are all the choices I have in Voukoder. Your system will vary, so if you have no AMD GPU, there's no VCE. QSV only works with certain Intel processors and their iGPUs. My only hardware accelerated choice is NVENC (NVIDIA) h.264.

 

Thanks friend. I will play around and read about encoding. You help me a lot.

Thanks too you and all others that are very active and ready to help newbies like me :)