Hi everyone i have a quick question i have a mtx amp briged at 200w (Dinamic Power) X 2 at 4 ohms @14.4 volts i can also run it at 100w X 2 at 4 ohms @12.5 volts
and i have a rockford fosgate 300w 12" 8 ohm sub woofer i was wondering thogh the ohmage is different wll either of these setups work without burning anything up? what will the results be? will the speaker have more power or will it burn the amp up? or will the speaker have less power?

You won't have trouble burning anything up, as long as you set your gains properly. With an 8 ohm sub you will be getting roughly half of what your amp is rated at 4 ohms. What model of amp is it? if you only have the one sub and assuming it's a bridgeable amp you could bridge the two channels and get as much power out of that amp as you can with that sub.

ive burnt channels running an amp at 8 ohms and up so be careful