Stepper motor not moving :)

Hello! 

I installed LinuxCNC 2.9.4 on a Dell optiplex 790 PC. I attached a parallel port card to the PCI slot and connected a BOB to it. I attached a single  DM556 driver and a 57BYGH76-8 Nema 23 stepper motor to the X axis following the recommendations for the wiring(attached photos) but the stepper motor is not moving. The motor is powered (it's impossible to turn it by hand when the power supplies are connected). I tried to remove the GPU (Gigabyte NVIDIA GeForce GTX 660) but the stepper is still not working but the OS is running better (before this when I tried to do a Latency Test the OS crashed a several times).
Do you have any suggestions?

Thank you,

Adrian

Powering the enable input disables the drive; perhaps that's the problem.

Leave the driver's enable pins unconnected or shorted together.

See if that fixees your problem.

Why would removing the GPU help?

A dedicated GPU can actually improve latency and performance.

But make sure all your monitor(s) are connected to the NVIDIA if it is installed.

I removed ENA+ and ENA- connections and also in StepConfig I disabled P14 but still the stepper motor is not moving. Before I used the P14 as Amplifier Enable. Thank you!