Another Sainsmart TFT Question

I tried searching the forums and google but I couldn't seem to find an answer.

I just bought this http://www.amazon.com/gp/product/B008FWSH3C/ref=oh_details_o00_s02_i03 and plugged everything in and hooked it up to my computer. Upon plugging in the unit to the USB port the screen does not power up. I also have a 9vdc 650ma wall adapter, so I tried that as well. Still nothing. I noticed that there is a pot on the side of the shield, so I thought maybe this was a dimmer pot. I have adjusted it in both directions and nothing happens. So I unhooked everything and then loaded the Blink sample code. That worked just fine.......

So do I have a bad LCD unit? Bad Interface Board? Any suggestions?

Thanks in advance,

Grimm

The screen will not do anything unless you have the proper library and sketch loaded into the Arduino.

This thread uses that screen, it has many helpful links in it. http://arduino.cc/forum/index.php/topic,54196.0.html