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DjDemonD
So under each a4988 is a 3x2 jumper header. All three need to be populated in order to get 1/16 microstepping. With none present you are on full steps. Unless you have a ramps from a dodgy batch where these jumpers have been connected by traces on the pcb and are redundant and locked to 1/16. (oddly the manufacturer included the jumper headers and fancy coloured jumpers on the board I had with this fault so it can't be intentional).

Make sure you identify the two pairs in each set of 4 motor cables, the colours of the wires are not reliable. Check the 4 motor cables resistance to determine the pairs. One pair go to pins 1&2 on the ramps motor connector and the other obviously to pins 3&4, which pair occupy each side of the connector determines motor direction. But firmware can reverse it also.

The motor current is best set using a voltmeter placed very carefully onto the trim pot measuring dc volts with the ground to the negative of the psu. Aim for 0.4v for starters that should make most reprap typical nema 17s turn reasonably well. Fine tune them later but that's usually a safe setting to know your not hopelessly under powering then or cooking them.

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VDX
... seems you try to move it faster than possible, so it stalls - try to reduce the max. speed ...