Specifications

1–4 Introduction to the AlphaPC 164 Motherboard
Subject to Change – 17 January 1997
System Components and Features
Table 1–1 Main Memory Sizes
1.1.3 L3 Bcache Subsystem Overview
The AlphaPC 164 board-level L3 backup cache (Bcache) is a 1MB, direct-mapped,
synchronous SRAM with a 128-bit data path. The board is capable of handling an L3
cache size of 2MB.
1.1.4 PCI Interface Overview
The AlphaPC 164 PCI interface is the main I/O bus for the majority of functions
(SCSI interface, graphics accelerator, and so on). The PCI interface has a 33 MHz
data transfer rate at all supported microprocessor speed BINs. PCI-IDE support is
provided by an onboard controller chip (CMD646). An onboard PCI-to-ISA bridge
is provided through an Intel 82378ZB Saturn-I/O (SIO) chip.
The PCI bus has four dedicated PCI expansion slots (two 64-bit and two 32-bit).
Total Memory
128-Bit Data Bus Width
with 4 SIMMs of Size...
16MB 1Mb
X
36
32MB 2Mb
X
36
64MB 4Mb
X
36
128MB 8Mb
X
36
256MB 16Mb
X
36
Total Memory
256-Bit Data Bus Width
with 8 SIMMs of Size...
32MB 1Mb
X
36
64MB 2Mb
X
36
128MB 4Mb
X
36
256MB 8Mb
X
36
512MB 16Mb
X
36