It should be noted that those are two different types of frames. One is the IVRNG, which as the name implies, controls the IVs. Wandering NPCs don't affect this at all in Generation 5, but withdrawing Pokémon does. Battles advance the IVRNG by about 120 fps, and walking 128 steps will advance it by however many Pokémon are in your party.
Originally Posted by Dangertrout
The PIDRNG is the RNG that controls gender, nature, ability, if it's shiny or not, encounter slot, and if it's holding an item (if that's applicable to species being encountered). That is advanced by WNPCs, as well as turning in the grass, or taking a step in the grass (two frames for each).
Finally, the seed is determined when you start the game, and won't change unless you activate the C-Gear in BW1.
[21:32] <@Kaphotics> Found trash bytes from evo chain Roggenrola, Gigalithe.
[21:32] <@Kaphotics> >>Found trash bytes from Gigalithe.
[21:32] <@Kaphotics> wut