update

sudo emerge --unmerge nvidia-drivers

##update kernel      ## BUILD NOUVEAU firmware directly in kernel !!!!
# Add
KERNEL Enabling nouveau
Device Drivers  --->
   Graphics support  --->
      <*> Direct Rendering Manager (XFree86 4.1.0 and higher DRI support) --->
         <*> Enable legacy fbdev support for your modesetting driver
      <*> Nouveau (NVIDIA) cards
# Rm ?

# after kernel update
emerge --ask sys-firmware/nvidia-firmware

/etc/portage/make.conf Set VIDEO_CARDS to nouveau
VIDEO_CARDS="... nouveau ..."

emerge -avuND @world

remove /lib/udev/rules.d/99-nvidia.rules if exists

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