Intel STL2 manual 2.1.2Dual Processor Operation, 2.1.3PGA370 Socket, 2.1.5Termination Package

STL2 Server Board Architecture Overview STL2 Server Board TPS

2.1.2Dual Processor Operation

The Pentium III processor interface is designed to be MP-ready. Each processor contains a local APIC section for interrupt handling. When two processors are installed, both processors must be of identical revision, core voltage, and bus/core speeds.

2.1.3PGA370 Socket

The STL2 server board provides two PGA370 sockets. These are 370-pin zero-insertion force (ZIF) sockets that a flip chip pin grid array (FC-PGA) package technology processor plugs into.

2.1.4Processor Bus Termination / Regulation / Power

The termination circuitry required by the Intel Pentium III processor bus (AGTL+) signaling environment, and the circuitry to set the AGTL+ reference voltage, are implemented directly on the processor. The STL2 server board provides VRM 8.4 compliant DC-to-DC converters to provide processor power (VCCP) at each PGA370 socket. The server board provides an embedded VRM for the primary processor and a VRM socket for the secondary processor. These are powered from the +5V supply.

2.1.5Termination Package

If a processor is not installed in a PGA370 socket, a termination package must be installed in the vacant socket to ensure reliable termination.

2.1.6APIC Bus

Interrupt notification and generation for the processors is done using an independent path between local APICs in each processor and the I/O APIC located in the IB6566 South Bridge component.

2.1.7Boxed Processors

The Intel Pentium III processor for the PGA370 socket is offered as an Intel boxed processor. Intel boxed processors are intended for system integrators who build systems from a server board and standard components.

2.1.7.1Boxed Process Fan Heatsinks

The boxed Pentium III processor for the PGA370 socket will be supplied with an unattached fan heatsink that has an integrated clip. Clearance is required around the fan heatsink to ensure unimpeded airflow for proper cooling. Note that the airflow of the fan heatsink is into the center and out of the sides of the fan heatsink. The boxed processor thermal solution must be installed by a system integrator to secure the thermal cooling solution to the processor after it is installed in the 370-pin ZIF socket.

The boxed processor’s fan heatsink requires a +12V power supply. A fan power cable is attached to the fan and connects to processor fan headers on the STL2 server board.

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