In the Arduino s/ware, there's a simple program you can upload which just makes an on-board LED blink - that should be a fair test of the board.
You can't do much really with the Ramps until you've plugged it into the Mega. Without the driver chips installed, you can test the heat output voltages, the end stops and the thermistors. All 3 "D" outputs have a corresponding LED which is a good indication that all is well when the outputs are energised. I would fit one of the pololu's in a socket and you can then test all the motors in turn with just that one. A ceramic s/driver is just a precaution, I don't use one coz I don't have one, I just made one out of a piece of plastic (like a knitting needle).
Info...
Put your heat sinks on - all the pololu chips and one on the hot end Mosfet.
Important: Examine both the boards with a magnifier to check for solder splash - you will find some although most if not all will be harmless. You can scrape the solder dots off with a finger nail or credit card or whatever works.
You can't do much really with the Ramps until you've plugged it into the Mega. Without the driver chips installed, you can test the heat output voltages, the end stops and the thermistors. All 3 "D" outputs have a corresponding LED which is a good indication that all is well when the outputs are energised. I would fit one of the pololu's in a socket and you can then test all the motors in turn with just that one. A ceramic s/driver is just a precaution, I don't use one coz I don't have one, I just made one out of a piece of plastic (like a knitting needle).
Info...
Put your heat sinks on - all the pololu chips and one on the hot end Mosfet.
Important: Examine both the boards with a magnifier to check for solder splash - you will find some although most if not all will be harmless. You can scrape the solder dots off with a finger nail or credit card or whatever works.