a lower resolution would make sense since you essentially have more "cache" left over. Because thats all the memory is at this point. But I think nobody is disputing the fact that its easier to develop games in 720p than in 1080p.
The question is how big the drawback would be. There is 256mb VRAM.
The framebuffer is 1920*1080 * 3b ~ 6mb.
Then you have z Buffer ~ 6 mb
Depending on you blending needs at least an o additional puffers (stencil, HDR rendering ...)
so in total I don't know 24mb? vs. 12mb for 720p
Other used buffers for example for shadow mapping do not depend on the output resolution. So I am not sure if the higher resolution would be that terrible if you look at it from a memory standpoint.
I would think that the fact that you suddenly have twice the screen pixels in 1080p i.e. that your shader and texturing pipelines have suddenly only 50% time per pixel is a bigger problem. But honestly I have no idea.
