Why are manufacturers so reluctant to change model numbers when they add features?

[foroplus]

Well, in fact, the differences between FX-7000G, GA, GB, and 7200G are more than that that you can appreciate at a simple glance like the color of the bezel or the color of the keys.

Internally, they have different motherboards and CPUs. Model 7000G and 7200G sport the chip NEC D1007G, while the GA sports the D3050G(AKA Hitachi HD62076). Though obviously that CPUs have to be very similar and almost equivalent.

Regarding power consumption, the figures are 7000G(7200G?):0.07W and 7000GA/GB:0.04W.