While the 2d Card includes the basic processing bundle with every card, you can add a +DSP license to your box at any time. Adding a +DSP license will allow you to take advantage of the greatly increased processing power of the new DSP and the ease of inserting Plug-ins directly into mixer channels. If your unit is already a +DSP unit, then you already have a +DSP license. But if your unit doesn't already include +DSP, you can add a license without any additional physical changes to your hardware.
The +DSP license includes a variety of additional Plug-ins including Multi-band EQs, Compressor, Limiter, Distortion Processors, and many more. With the +DSP license, you also gain access to insertable graphs which allow you to build your own "Secret Weapon" processors - wrapped up, phase compensated graphs of Plug-ins that may be re-inserted on demand.