Max acceleration - for motor or driver?

I have my home made set up working and am doing some fine tuning?

Nearly time to mount it in a case and bolt the motors on the mill

My X axis is a direct drive, 1:1 and Y and Z are using toothed pulleys 1:2

I have found that the default acceleration and velocity values in stepconf cause the
Y motor to stall (and make a strange noise) so I have used the 'test axis'
to lower this to a value that seems to work without problems but am wondering
how to work out the correct values - is this related to the driver board (a home
built one based on a 6064AH chip and kit) or the actual stepper motor
(an FL86STH80-4208A-H from motioncontrolproducts.com)

The X axis values are set much higher without problems which I am guessing
is due to the 1:1 ratio?

The step timings are shown below - based on the settings from the Linistepper
which uses the same 6064AH chip - although the Gecko settings work too?

Step time 2300ns
Step space 2300ns
Direction hold 4600ns
Direction setup 1000ns

Thanks in advance

Chris Parsons