Power Issues, RAMPS 1.4, 12v 30amp supply

Okay, so I'm totally new to 3d printing and my only background is in programming. Answers will definitely need to be "like I'm 5"...

So I finished putting together a Prusa from MakerFarm, [www.makerfarm.com], using the prebuilt RAMPS 1.4 kit. I am powering it with the USB connection and one these 12v 30a power supplys:
[www.newegg.com]

Loaded it with the Sprinter firmware and can successfully connect to it with Pronterface, but that is where the success ends. Nothing moves, no humming, nothing at all.

So far my troubleshooting has consisted of:
Tested the terminals from the power supply and they are giving 12v.
Removed all motor/hot ends/thermistor connections one at a time, no change.
Removed everything leaving ONLY the X-axis motor connected, no change.

Here is the console output from Pronterface:
Connecting...
Sprinter
1.3.22T / 20.08.2012
start
Printer is now online.
SD Start
SD init fail
Soft PWM Init
Planner Init
Stepper Timer init
Free Ram: 4158
Plan Buffer Size:1152 / 16

So - where do I go from here? I'm guessing the power supply is the issue, but I'm not sure where to start looking for issues. Open to any ideas. Let me know if I should post any pictures or additional information. Thanks!

Edited 1 time(s). Last edit at 03/21/2013 03:04AM by aaroninaustin.

Basics first, no insult intended.

I use Marlin firmware, and when configuring it, one must specify the board type (33 for RAMPS), then in pins.h define the appropriate RAMPS version macro. I don't know if Sprinter has this same process, but if so, double check what the settings (board and pin assignments) are.

Is the 12V tied into the 5A input on the RAMPS board? This is important because the 11A input ONLY powers the bed heater (D8 output).

Are the Polulu drivers installed on the RAMPS board, in the right orientation? Did you set their potentiometers to 25%? (turn CCW all the way, then CW to 25% of their range)

When I was testing my hardware, being new to 3d printers too, I was very cautious. I removed all the polulu drivers except for the X axis. That way, in case I made a mistake somewhere the worst case is I blow one driver.

Edited 1 time(s). Last edit at 03/22/2013 06:14PM by BrentB.