I'm wondering whether some of you would have tested and seen quite a difference in using a compressed texture even when the OpenGL environment does not need saving any memory (i.e. the card has more memory than necessary to support the textures uncompressed.)
I'm thinking that a compressed texture would use less RAM and thus reading it and decompressing in the GPU would be faster because the number of memory accesses is lower. Whereas, a non-compressed texture would rely more on memory access (GPU I/O) than processing and that is likely slower.
The main things I've read about texture compression has been about how the compression saves space. Not so much about how it can save execution time with the GPU. (Note that I specifically will be using an nVidia, Pascal for now. But I would hope that it works similarly whatever the GPU.)