Checkerboard rendering
Shade only every other pixel in a checkerboard pattern each frame and reconstruct the rest from earlier frames — a way to approach 4K at half the fill cost.
Rather than shade every pixel, the technique renders half of them in a checkerboard pattern and fills the empty squares by blending in last frame's values, reprojected with motion vectors. It became well known with the PlayStation 4 Pro (2016), which used it to deliver near-4K output without doubling the fill-rate bill.
At heart it is a form of temporal reprojection, and it suffers the same artefacts — ghosting and unstable edges in fast motion where the old data no longer matches. It was largely superseded by machine-learned upscalers such as DLSS.