Ensure your system is up to date by running:

   sudo emerge --update --deep @world

Make sure you are using the latest kernel for better graphics support. You can update it with:

   sudo emerge @module-rebuild
   sudo genkernel all --menuconfig

During the menuconfig step, ensure that your GPU driver is properly configured and enabled. If needed, enable proprietary drivers if you are using NVIDIA or AMD cards.

Edit your X11 configuration file (usually `~/.xinitrc` or `/etc/X11/xorg.conf`) to ensure the correct graphics driver is loaded. For example, for an NVIDIA card:

   sudo nano /etc/X11/xorg.conf

Add a section like this:

   Section "Device"
       Identifier  "nvidia"
       Driver      "nvidia"
       VendorName  "NVIDIA Corporation"
       BoardName   "GeForce GTX XXX" # Replace with your GPU model
   EndSection

Ensure you have a compositor installed, such as `compton` or `picom`. Install it using:

   sudo emerge compton picom

Then configure your preferred compositor in your X11 configuration file (e.g., `~/.xinitrc`):

   if [[ -z $DISPLAY && $XDG_VTNR -eq 1 ]]; then
       exec startx -- /usr/bin/Xorg -noreset +extension GLX +render -logfile "~/.xorg$(tty).log" -config ~/.xorg.conf
   fi

For `compton`, add the following line to your `.xinitrc`:

   compton --config /etc/compton.conf &

If you are using proprietary drivers (e.g., NVIDIA), ensure they are correctly installed and configured. You can check the status of your graphics drivers with:

   lspci -k | grep -EA3 'VGA|3D'

If you have added or updated hardware, you may need to rebuild your graphics drivers:

   sudo emerge @module-rebuild
   sudo genkernel all --menuconfig

After making these changes, restart your system and check if the issue is resolved:

   sudo reboot

If you continue to experience issues, consider checking the logs in `/var/log/Xorg*.log` for more detailed error messages that can help diagnose the problem.