Thanks for the speedy replies.
The motors are 500 ma and there are two of them.
The power supply is 12 volt and 1.5 amp.
I swapped it for another 1.5 amp and it did the same.
I changed the two A4988 drivers for another 2 new ones and got the
same result.
I tried different speeds but no change, and it is not running fast at all.
I tried to run the motors in the CONTROL box and when I click on
any X, Y or Z it moves about 1 full rev with each click.
If I increase the number to 10 the selected motor rotates about 3
revs then vibrates for about 4 revs, then rotates for the remaining amount.
I also noted that if I send the motors to a position that is
diagonal from the start point, then I tell it to go to origin then
both motors vibrate with no rotations while the pointer on screen
moves towards the origin.
At any time, I can't seem to get both motors rotating at the same time.
Even with the circle, one motor stops before the other starts.
I would assume that to produce a smooth, round object,
both motors will have to rotate together at different speeds
As if you haven't guessed, I an a novice at this but it seems to
me that it is not a hardware problem because of all the changing
of components with the same results.
Maybe there is something that I failed to do (or did wrong) when
installing Arduino IDE or G code or either of the G Code senders.
Any help is greatly appreciated.