cards (CA0106-WBTLF) and thus lacks the hardware acceleration of 3D sound and EAX sound effects, gaming and content creation features and the I/O extensibility of all the other X-Fi models. It is not marketed as supporting gaming or EAX. Creative also released an external solution (named x-mod) in November 2006 which is listed in the same category as the rest of the X-Fi lineup, but is only a stereo device, and lacks the specifications of the internal offerings. The 130 nm EMU20K1 audio chip operates at 400 MHz and has 51 million transistors. The computational power of this processor, i.e. its performance, is estimated as 10,000 MIPS (million instructions per second), which is actually about 24 times higher than the estimated performance of its predecessor—the Audigy processor. It is interesting to note that the processor’s computational power is optimized for the work mode selected in the software. With the X-Fi's "Active Modal Architecture" (AMA), the user can choose one of three optimization modes (Gaming, Entertainment, and Creation), each of which enables a different combination of the features of the chipset. The Xtreme Audio model lacks the EMU20K1 chip and thus only supports the "Entertainment" mode via software emulation, while all other models support all three modes. X-Fi models that support "Gaming" mode use EAX 5.0, which supports up to 128 3D-positioned voices with up to four effects applied to each. The X-Fi, at its release, offered some of the most powerful mixing capabilities available, and made it a powerful entry-level card for home musicians. The audio processor on X-Fi was by far the most powerful at its time of release, offering an extremely robust sample rate conversion (SRC) engine in addition to enhanced internal sound channel routing options and greater 3D audio enhancement capabilities.