GT 710 and H.264 on Client

[LiFeMaKeR]

Good Day!
Just today i bought a Nvidia GeForce GT 710 for a small and older Dell Desktop Machine, so that it can use Steam inHome Streaming with Hardware Decoding. Even though the Specifications clearly states that the GT 710 is capable of Hardware Decoding via H.264, the Steam Client is not able to initiate the Encode on the Client. And that is quite unfortunate given the fact that the CPU on that Machine is an Dual-Core, which results in 40% dropped frames @ 1080p60h. With 720p60h it's only 30%, but in both cases the sound starts to cracle.
The Log states:
[2017-09-09 15:35:50] >>> Client video decoder set to libavcodec software decoding with 2 threads
[2017-09-09 15:35:50] CLIENT: Video size: 1280x720, output size: 1920x1080

[2017-09-09 15:35:50] CLIENT: DXVA init resetting SDL renderer

[2017-09-09 15:35:50] CLIENT: DXVA: Using device NVIDIA GeForce GT 710

[2017-09-09 15:35:50] CLIENT: DXVA init failed: Couldn't find H264 hardware decoder

[2017-09-09 15:35:50] CLIENT: libavcodec software decoding with 2 threads

Anyone got an Idea?