Hello i have a eps8266 that i need to be able to control a 12v fan that is between 0.67 amp up to 0.76 amp. I was thinking of uing a Tip120 but not sure if that the esp8266 would be able to handle it. I need some help trying to figure out what would be best for these fans. Can someone please help to figure this out?
Joseph
A TIP120 is possible (don't forget the base resistor) but it's not the most efficient transistor. So I would rather get a logic level mosfet I think.
Hello which mosfet would i look for a N channel or P channel?
N, that's wayyyyy easier 
Maybe hard to find a TO-220 mosfet for 3.3volt logic.
A TIP120 with ~470ohm base resistor (and diode across the fan) is also ok here.
The TIP will drop almost one volt, but you will hardly notice that if you have 12volt available.
Might get a bit warm with 0.75A.
Leo..
Edit: All your mosfet questions are answered on this page.
Question, is the flyback diode necessary on a brushless fan motor?
That was another thing i was worried about is having to add a heat sink on it. Which would be okay i got room for one. The Diode is another thing I'm also wondering about?
Joseph
@0.75A collector current, and without heatsink, expect a temp rise of ~25C (45F) above ambient.
Diode might not be needed, but why worry about using a $0.05 (1N4004) diode.
You should have hundreds of diodes in stock if you have electronics as a hobby.
Plenty on old circuit boards in rubish/recycle places too if money is tight.
Leo..