Figure 1–3. Basic System Board - Compaq AlphaServer DS20E Reference Manual

System Overview 1-5
The system is housed in an enclosure containing the system board, other logic
modules, and two power supplies (maximum of 3) with internal fans. The
enclosure allows for internal mass-storage devices which includes a
combination IDE CD-ROM/floppy disk drive, one available half-height
removable bay, and four 1.6-inch hot-swap drive bays. The control panel
includes On/Standby and Reset, and Halt buttons. The system can be used
as a desk-side pedestal in the vertical position, or with the addition of brackets,
may be mounted in the horizontal position in a standard rack.
All memory and I/O components are on a single system board that contains a
memory subsystem, PCI bus, ISA bus, integrated SCSI F/W/U I/O controllers,
and option slots for PCI-based and ISA-based option modules. A separate
system management module serves to monitor and control the system
remotely.
The 21264 microprocessor is a superscalar, super-pipelined implementation of
the Alpha architecture and runs at an optimized price/performance speed of
500 MHz and above. The chip contains a 64 KB I set associative cache and a
64 KB D set associative cache. Support for a larger L2 Cache is provided by a
private cache (Bcache). 4 MB are standard with upgrade.
Figure 1–3 shows the basic system board.
CAT0030
Figure 1– 3. Basic System Board
Compaq Confidential – Need to Know Required
Writer: Robert Young Project: DS20E Reference Guide Comments:
Part Number: ER-K8F6W-UA .A01 File Name: b-ch1 System Overview.doc Last Saved On: 10/4/99 1:23 PM