Problems with my PowerSpec Ultra 3D printer?

I swapped the small stepper drivers around and found out that the extruder steppers are still clicking. Is the driver board bad? The driver board shown at http://www.flashforge.com/product/driver-board-dreamer/ has header for one extruder, not two.

The printer probably came in single and dual extruder models. I am not familiar with it.

Would a buying Robo3D printer be better than trying to fix my PowerSpec Ultra 3D printer?

Probably a failed or failing cable. Depending upon how technical you are, you could either buy a new cable harness or splice in a new length.

There is a known issue on all these family of printers where the wires are secured onto the extruder carriage. It concentrates all the bending into a small area and I think this is the problem you are having.

You may well find that eventually the heating and thermister wiring will fail at the same point as well.

Once you get it going, there is a fix here: http://www.thingiverse.com/thing:1549265 that you can print.

I tried swapping cables between steppers and driver board but steppers connected to extruder ports don't work and steppers connected to X, Y, and Z ports work. I don't have any spare cables.

If you have a meter, check the cables have good continuity. It sounds like this is the problem.

Stepper motor drives rarely go bad - and on many boards can be swapped over easily anyway, as they are on plugs and sockets. Try swapping over the extruder output to a stepper motor, so that a different cable is running from the extruder output on the board. This will prove if it is the stepper motor drive or the cable.

The cables can be bought as a spare part. Example here, but make sure you get the correct length and connector type. These fit most of the clones. http://www.3dprima.com/en/accessorie...tor-cable.html

I found out that the cables for the extruder steppers are bad. I found some cables belonging to different kind of stepper motors so I cut the cables off the stepper motors and spliced the cables into the cables coming out the bottom of the printer. While trying to load filament into one of the extruders, I broke the hothead tube while trying to remove the nozzle. I had to order new cables and extruder assembly from Flashforge company.

Glad you have found the fault.

Just out of interest, why did you need to remove the nozzle to load the filament? I've only needed to take nozzles off to replace a PTFE liner.

I was trying to load the filament into the extruder and I thought that the nozzle was clogged so I tried to remove the nozzle from the hothead but I broke the metal tube that holds the hothead to the bar that holds the extruder steppers and fans.

Surprisingly easy to do. It's tricky to hold the heater without damaging it, but I find a pipe wrench can be adjusted to the correct size and will hold the heater while you use an 8mm spanner on the nozzle.