NEC DIRECTION L Service Manual

Contents

Technical Information 1-5High-performance features include: pipeline 32-bit addressing 64-bit data 512-KB of pipeline burst secondary cache; direct mapped write-back andwrite-through organization.Depending on the model, the system comes with 32 to 192 MB of main system memory.Three sockets on the system board support up to 384 MB of high-speed memory usingindustry-standard gold-plated dual in-line memory modules (DIMMs).The system supports 60-ns Synchronous DRAM (SDRAM).The system supports the following 60-ns configurations: 1-Mbit by 64 or 72 (8-MB DIMM) 2-Mbit by 64 or 72 (16-MB DIMM) 4-Mbit by 64 or 72 (32-MB DIMM) 8-Mbit by 64 or 72 (64-MB DIMM) 16-Mbit by 64 or 72 (128-MB DIMM).ChipsetThe Intel 440LX chipset provides DMA, memory, and bus control. The chipset includes thefollowing chips: Intel 82443LX PCI/A.G.P. (PAC)  provides bus-control signals, address paths,and data paths for transfers between the processor’s host bus, PCI bus,Accelerated Graphics Port (AGP), and main memory. Intel 82371AB PCI/ISA IDE Xccelerator (PIIX4)  implements the PCI-to-ISAbridge, PCI IDE functionality, Universal Serial Bus (USB) host/hub functions,and enhanced power management.PCI Local BusThe 32-bit industry-standard PCI bus is a highly-integrated input/output (I/O) interface thatoffers the highest performance local bus available for the Pentium II processor. The PCI bussupports burst modes that send large chunks of data across the bus, allowing fast displays ofhigh-resolution images.The high-bandwidth PCI local bus eliminates data bottlenecks found in traditional systems,maintains maximum performance at high clock speeds, and provides a clear upgrade path tofuture technologies.