NVIDIA Whitepaper - Wikipedia Specs - Techreport Review
For framebuffer compression, looks like for 32-bit/pixel a block of 16x16 fragments gets compressed in 3 steps. Implies that samples for 8xMSAA are stored in 2x4 or 4x2 fragment blocks (depending on if the image or text description is correct), and samples for 4xMSAA stored in 2x2 fragment blocks. The three steps: (1.) 8:1 compression if the fragment values are all uniform for 2x4? or 4x2? blocks, (2.) 4:1 compression if fragment values are all uniform for 2x2 blocks, or lastly (3.) 2:1 compression if delta compression works out (stores deltas between fragments for less bits). Looks like Maxwell adds some more options for delta compression. Sounds like 8xMSAA shaded with a forced 2 samples per pixel would nicely fallback to the 4:1 compression case for blocks in triangle interiors. This compression ability is one of the major reasons MSAA is ultra fast on NVIDIA hardware.
Maxwell in the 980/970 has viewport multicast from VS without the need for GS, conservative raster, programmable sample positions for a repeating block of samples, and ability to stall the pixel shader to implement in-raster-order shader processing for a given pixel (could use for programmable blending for example).
For framebuffer compression, looks like for 32-bit/pixel a block of 16x16 fragments gets compressed in 3 steps. Implies that samples for 8xMSAA are stored in 2x4 or 4x2 fragment blocks (depending on if the image or text description is correct), and samples for 4xMSAA stored in 2x2 fragment blocks. The three steps: (1.) 8:1 compression if the fragment values are all uniform for 2x4? or 4x2? blocks, (2.) 4:1 compression if fragment values are all uniform for 2x2 blocks, or lastly (3.) 2:1 compression if delta compression works out (stores deltas between fragments for less bits). Looks like Maxwell adds some more options for delta compression. Sounds like 8xMSAA shaded with a forced 2 samples per pixel would nicely fallback to the 4:1 compression case for blocks in triangle interiors. This compression ability is one of the major reasons MSAA is ultra fast on NVIDIA hardware.
Maxwell in the 980/970 has viewport multicast from VS without the need for GS, conservative raster, programmable sample positions for a repeating block of samples, and ability to stall the pixel shader to implement in-raster-order shader processing for a given pixel (could use for programmable blending for example).