I have a 9v adapter that I hooked up to negative and positive wires to power my Arduino with.
But, I heard that powering through the VIN pin bypasses the regulator and could fry my board.
If I solder the negative and positive wires of my adapter to the correct pins UNDERNEATH the DC Jack, will the power I send go through the regulator?\
I think what you may have heard was that 'powering your Arduino through the 5V pin bypasses the regulator, and could fry your board.' The VIN pin is there for exactly the purpose of powering your board with a 6 to 12 volt* supply.
Larry posted the schematic that explains how it's all hooked up on the board.
- actually up to 20 volts, but then it'll get hot.