At 12 volts the motor current should be about 1.4 Amps with no load on the motor. Overall:
Operating v : 6v - 14.4v
Nominal v : 12v
No Load RPM : 19300
No Load A : 1.4A
I realize no scope but are you monitoring the voltage to the motor when you try to power it?
Additionally, and I am not sure but I believe when you PWM you are still applying the voltage of whatever. However, the average current will be lower.
Anyway, back to now, I would guess for some reason the laptop adapter is folding over, it may not like the start load of the motor. My reference to 3 wire was on the adapter output, some have three wire outputs.
Ron