L298N + stepper overheating!

Not sure if this is the correct part of the forum but my dilemma concerns excessive heat development in a stepper.

Im trying a bipolar 200 stepper motor 12v with L298n through arduino uno. Is there a better driver for this task?
If id use a resistor, wouldnt that effect the speed of my motor? My goal is to power it to speed 100 rpm at least without an enormous temperature rise.

Powering through 5-12 v dc adapter.

Any suggestion is greatly appreciated.

The L298 is a really bad stepper driver. Pololu has a good line of modern stepper drivers. For those drivers, you will need at least 8V motor power supply, more is better up to the max for the driver.

What is the rated coil current of the motor? Do you have a data sheet?

The motor is

Rated Current: 1,7A
Phase Resistance: 1,5Ohm
Phase Inductance: 2,8mH

Would DRV8825 be a better driver?

Would I be able to link the arduino to the DRV8825 without the breadboard, capacitor as in this setup: