NEC NEAX Express, Service & Reference Manual

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System Overview 1-9
Processors
Depending on system configuration, each system may include one or two processors.
Each processor is packaged in either a Single Edge Contact Cartridge (SECC) or Single
Edge Contact Cartridge 2 (SECC2) package. The cartridge includes the processor core
with an integrated 16 KB primary (L1) cache; the secondary (L2) cache; a thermal
plate; and a back cover. The processor implements the MMX
™
technology and the
processor’s numeric coprocessor significantly increases the speed of floating-point
operations.
The processor external interface is MP (Multi-Processor) ready and operates at a
maximum of 100 MHz. The processor contains a local APIC (Advanced Programmable
Interrupt Controller) section for interrupt handling in MP and UP (Uni-Processor)
environments.
The second-level cache is located on the substrate of the processor cartridge. The cache
includes burst pipelined synchronous static RAM (BSRAM). The L2 cache is offered in
512 KB configurations only, with error correcting code (ECC) that operates at half the
core clock rate.
System Memory
The system board contains four 168-pin DIMM sockets. Memory is partitioned as four
banks of SDRAM DIMMs, each providing 72 bits of noninterleaved memory (64-bit
main memory plus ECC). Your system may include from 32 MB to 1 GB of memory,
using up to four DIMMs.
System memory begins at address 0 and is continuous (flat addressing) up to the
maximum amount of DRAM installed (exception: system memory is noncontiguous in
the ranges defined as memory holes using configuration registers). The system supports
both base (conventional) and extended memory.
Note: Memory should be added in order from slot 1 to slot 4.
Note: Use DIMMS currently available from the Approved
Vendors List (AVL) only. Contact your NEC sales representative or
dealer for the current AVL of memory modules (DIMMs) available for
your server.