Jack

wow long post.

A couple of questions....

Using your example scenario where the cpu writes data pointer to memory and the gpu takes this data to further process it.
Assuming the gpu is slower getting the data from memory than the cpu is writing.

You said:
Conversely, what happens if the GPU is late to the buffer and the CPU picks the same write pointer as before ... does it over write? Nope, it waits....


Doesnt this mean that when the CPU waits that the particular task which writes the data to memory is idle during that short period of time?
Wouldnt it mean that overall in such case you should see a slight drop in CPU utilization?

You said:
If I run a game sequence at very low resolution then again at very high resolution, should I see a load change on the CPU since it will need to wait on the GPU? Hmmmm food for thought.

I guess yes see above.

Some other thoughts:
CPU limited in this case would probably mean that the CPU calculations are not fast enough producing results for the task which writes the result into memory.

Also dont underestimate changing resolution on the gfx as well as detail level does affect GPU performance. So in worst case you could drift from an GPU bound to an CPU bound case. e.g. GPU is just a little quicker in reading the CPU data where the GPU operates at low resolution.
When resolution is suddenly set to high the GPU cannot grab the new memory data as quick as before because it is suddenly framebuffer bandwidth limited and now the CPU provides the data quicker than the GPU can process it.