1. x11-drivers/nvidia-drivers, media-libs/libva, media-video/libva-utils 설치 확인

eix -I# "nvidia-driver|libva|libva-utils"
media-libs/libva
media-video/libva-utils
x11-drivers/nvidia-drivers

vainfo
Trying display: wayland
libva info: VA-API version 1.22.0
libva info: User environment variable requested driver 'nvidia'
libva info: Trying to open /usr/lib64/va/drivers/nvidia_drv_video.so
libva info: Found init function __vaDriverInit_1_0
libva info: va_openDriver() returns 0
vainfo: VA-API version: 1.22 (libva 2.22.0)
vainfo: Driver version: VA-API NVDEC driver [direct backend]
vainfo: Supported profile and entrypoints
      VAProfileMPEG2Simple            : VAEntrypointVLD
      VAProfileMPEG2Main              : VAEntrypointVLD
      VAProfileVC1Simple              : VAEntrypointVLD
      VAProfileVC1Main                : VAEntrypointVLD
      VAProfileVC1Advanced            : VAEntrypointVLD
      VAProfileH264Main               : VAEntrypointVLD
      VAProfileH264High               : VAEntrypointVLD
      VAProfileH264ConstrainedBaseline: VAEntrypointVLD
      VAProfileHEVCMain               : VAEntrypointVLD
      VAProfileVP8Version0_3          : VAEntrypointVLD
      VAProfileVP9Profile0            : VAEntrypointVLD
      VAProfileAV1Profile0            : VAEntrypointVLD
      VAProfileHEVCMain10             : VAEntrypointVLD
      VAProfileHEVCMain12             : VAEntrypointVLD
      VAProfileVP9Profile2            : VAEntrypointVLD
      VAProfileHEVCMain444            : VAEntrypointVLD
      VAProfileHEVCMain444_10         : VAEntrypointVLD
      VAProfileHEVCMain444_12         : VAEntrypointVLD

3. /etc/environment.d/12-nvidia.conf 환경 변수 설정

LIBVA_DRIVER_NAME=nvidia
MOZ_DISABLE_RDD_SANDBOX=1
NVD_BACKEND=direct

4. Firefox에서 about:config 페이지에서 옵션 설정

• media.ffmpeg.vaapi.enabled → true
• media.hardware-video-decoding.force-enabled → true
• widget.dmabuf.force-enabled → true
• gfx.webrender.all → true

5. nvtop 등으로 DEC, GPU, CPU 등의 사용량 확인.