Dell OptiPlex GX1 Service Manual page 159

You can upgrade video memory from 4 to 8 MB by installing a video-memory
upgrade module in the video-memory upgrade socket on the system board.
Adding additional video memory increases the system's video performance
and provides additional modes for high-resolution/expanded color applications.
To install the video memory upgrade, follow these steps:
NOTE: If you do not hear a sharp click when installing the video-memory
upgrade module, remove the module and repeat steps 2 and 3.
NOTE: As the system boots, it automatically detects the presence of the
new video-memory upgrade module and automatically changes the sys-
tem configuration information in the System Setup program.
Removing and Replacing Parts on the OptiPlex NX1 Net PC Chassis
video-memory video-memory
upgrade module
upgrade socket
notch
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