Those subs are single 4-ohm? If thats the case, you pretty much have only one option with that amp: wire each sub to its own channel. So you would only be getting 200w rms to each sub. In your case, I would suggest you sell that amp and get a nice mono amp that does 600w rms @ 2-ohms. Then wire your subs parallel(connect all postives to positive terminal on the amp, and all negatives to negative terminal on the amp), you will have a 2 ohm load.