competitive advantage. In newer variants (like the slim edition), the interface would however, offer vastly more bandwidth than what is required by the PlayStation's input output devices as the HDD support was removed and the PCMCIA connector design was abandoned in favor of a slimmer design. Fabrication The Emotion Engine contained 13.5 million metal–oxide–semiconductor (MOS) transistors, on an integrated circuit (IC) die measuring 240 mm2. It was fabricated by Sony and Toshiba in a 0.25 µm (0.18 µm effective LG) complementary metal–oxide–semiconductor (CMOS) process with four levels of interconnect. Packaging The Emotion Engine was packaged in a 540-contact plastic ball grid array (PBGA). Uses The primary use of the Emotion Engine was to serve as the PlayStation 2's CPU. The first SKUs of the PlayStation 3 also featured an Emotion Engine on the motherboard to achieve backwards compatibility with PlayStation 2 games. However, the second revision of the PlayStation 3 lacked a physical Emotion Engine in order to lower costs, performing all of its functions using software emulation performed by the Cell Broadband Processor, coupled with a hardware Graphics Synthesizer still present to achieve PlayStation 2 backwards compatibility. In all subsequent revisions, the Graphics Synthesizer was removed; however, a PlayStation 2 software emulator is available in later system software revisions for use with Sony's PS2 Classics titles available for purchase on the Sony Entertainment Network. Technical specifications Clock frequency: 294 MHz, 299 MHz (later versions) Instruction set: MIPS III, MIPS IV subset, 107 vector instructions 2-issue, 2 64-bit fixed point units, 1 floating point unit, 6 stage pipeline Instruction cache: 16 KB, 2-way set associative Data cache: 8 KB, 2-way set associative Scratchpad RAM: 16 KB Translation look aside buffer: 48-entry combined instruction/data Vector processing unit: 4 FMAC units, 1 FDIV unit Vector processing unit registers: 128-bit wide, 32 entries Image processing unit: MPEG2 macroblock layer decoder Direct memory access: 10 channels VDD Voltage: 1.8 V Power consumption: 15 W at 1.8 V Embedded memory: 1KB RAM, 4KB FeRAM, 16KB ROM Theoretical performance Floating-point: 6.2 billion single-precision (32-bit) floating-point operations per second Perspective transformation: 66 million polygons per second With lighting and fog: 36 million polygons per second Bézier surface patches: 16 million polygons per second Image decompression: 150 million pixels per second See also Graphics card Graphics processing unit Computer graphics List of computer graphics and descriptive geometry topics Cell microprocessor, a design inspired by the Emotion Engines' CPU+VU0/VU1