Is HDR "Free" for the Xenos?

[reptile]

The ROP's are fully orthogonal so Multi-Sampling can operate with all pixel formats supported.[Edit: Which in context is clearly both FP16 and FP10]

I wouldn't be surprised, if it turned out, that only RT formats with blending ability could be used with MSAA... INT16 is a good candidate for that.

 

[hongcho]

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It's odd that there would be a significant drop with FP16 + MSAA, but not so much with FP16, though.
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I wouldn't find it so odd. Rather, it is somewhat telling about the architecture.

FP16 (64-bit pixel) would require twice the frame buffer as FP10 (32-bit pixel) or twice the number of tiles. If the number does not go down that much in this case, it probably means that the system has enough bandwidth to move around tiles that many.

I think MSAA adds loads on the shader (although the bandwidth issue is taken care of by "smart" eDRAM). Maybe, the shader pipeline cannot handle multiple passes of 64-bit values as well as those of 32-bit values.

Just a guess.

Hong.