1. Bootloader doesn't matter as long as you can upload a firmware.
2. Try to move slowly, like 100 mm/min. If this works, your motors are wired correctly. If not, see [reprap.org]
3. Adjust current. See [reprap.org]
4. If you still can't move fast, reduce acceleration. Default acceleration in Marlin is way too high for most setups.
2. Try to move slowly, like 100 mm/min. If this works, your motors are wired correctly. If not, see [reprap.org]
3. Adjust current. See [reprap.org]
4. If you still can't move fast, reduce acceleration. Default acceleration in Marlin is way too high for most setups.