One of the nifty new unsung features of K20 is the ability to set the GPU Operation Mode (GOM) to be compute only, allow low precision graphics, or full graphics. This is a power saving option since disabling the graphics functions may lower chip power use.
Unfortunately this mode is only controllable with K20m, not with K20c. This is mentioned in
library API documentation.
Neither the K20c or K20m has video out, but the graphics hardware could still be used for offscreen rasterization. (I can make high resolution shadow maps for volumetric raytracing, for example.)
But why is changing the GOM mode restricted for K20c but not K20m?