It is not clear if those LEDs are common anode or common cathode.
Look at the picture of the LEDs... you see R+, G+, B+, and - on the PCB. I would guess at common cathode from that.
The drives are based around the AMC7135. The data sheet quotes:
350mA constant sink current.
and there are three on each "chip" (as dealextreme call it). Even so, DE quote
- 4W 1050mA (+/- 10%) Regulated Power Output
So I don't know what they're on about there... (yes, that is 3 chips worth of sink - but power output?! The chip sinks!)
One of the comments on the deal extreme site was:
The screen is wrong, + and - symbols are interchanged. This LED is common anode. Simply change your transistors from NPN to PNP.
Each color draws a different current, so you cannot use a common resistor.
Sorry if I'm a little n00b at all this