2 System Board
Devices on the Processor-Local Bus
| Devices on the |
| The Intel Pentium Microprocessor |
| The Pentium processor is packaged in a |
| seated on the system board in a |
| upgrades that are pin compatible with the original processor, manufactured |
| by Intel, are supported. |
| P54CS chips working at 133 and 150 MHz (along with P54C chips working at |
| 75, 90, 100 MHz and new versions of the 120 MHz chip) require a 3.3 V |
| supply. A passive shorting block is sufficient to connect the regulated 3.3 V |
| output of the power supply directly to the Pentium processor. |
| P54CS chips working at 166 and 200 MHz require between 3.45 and 3.60 V. |
| They need an VRE voltage regulator module (VRM), in which the voltage |
| is actively derived from the 3.3 V, 5 V and 0 V outlets of the power supply. |
| P55C chips, with MMX technology, require two voltage supplies: 3.3 V for |
| the input and output buffers, and 2.8 V for the core logic. It requires an |
| active VRM that is specifically designed for use with the MMX processor. |
| This VRM can be identified by the inscription “2.8 V” marked on the board. |
| Any thermal contact material between the processor and the |
| not be removed or disturbed. The cooling needs of the processor are critical. |
MMX Technology | The instruction set of the MMX processor includes 57 new instructions, four |
| new |
| registers. As well as the pipelined parallelism of the traditional Pentium |
| architecture, MMX is capable of SIMD parallelism |
| |
| result, each instruction is able to gang each operation over a large number of |
| pairs of operands, so producing a large number of results concurrently. This |
| type of parallelism is particularly useful when processing large vectors and |
| arrays of data (in graphics and audio processing, for example). |
Quadword
64 bit
Packed double word
32 bit
32 bit
Packed word
16 bit
16 bit
16 bit
16 bit
Packed byte
8 bit
8 bit
8 bit
8 bit
8 bit
8 bit
8 bit
8 bit
30
