For human ears, we require a 10db increase for a perceived doubling of volume.
3db increase in audio requires twice the amount of power to produce (i.e. double the wattage on a speaker amplifier), but does not sound twice as loud, not nearly.
You're remembering it incorrectly.
There were two types of 9500 non-pros. One had an L shape memory layout (2 chips above and beside the GPU), the other had all the memory chips in a row. If it had the L shaped layout, you could flash it to 9700 and unlock all 8 pixel pipelines and the full...