DEC 3000 Model 400 AXP Technical Summary

This document is a technical summary of the DEC 3000 Model 400/400S AXP system, detailing its architectural features, implementation, and performance.

Key aspects include:

1. System Overview:

   • Powered by Digital's 64-bit Alpha AXP architecture and implemented by the 133 MHz DECchip 21064 RISC microprocessor, featuring on-chip 8KB instruction and data caches, and a 512KB on-board secondary cache.
   • Available as a workstation (including graphics and monitor) or a server (without graphics/monitor, requiring a serial terminal).
   • Supports up to 128 MB of memory (expandable to 512MB) with ECC.
   • Features high-performance TURBOchannel slots (three available, one typically for graphics) for expansion, supporting 2D/3D graphics, multimedia, and third-party options.
   • Includes SCSI-2 for storage, AUI and 10BASE-T Ethernet for networking, and built-in audio capabilities.

2. System Software:

   • Supports two primary operating systems: OpenVMS AXP (known for ease-of-use, security, distributed computing, and windowing) and DEC OSF/1 AXP (Digital's UNIX implementation, compliant with OSF AES, POSIX, and binary-compatible with ULTRIX).
   • Offers a full suite of software development languages (Ada, C, COBOL, FORTRAN, Pascal) and the DEC FUSE integrated software engineering environment.
   • Utilizes DECwindows Motif as its industry-standard graphical user interface, built on the X Window System.
   • Provides comprehensive graphics programming interfaces including Xlib, Display PostScript, ANSI/ISO PHIGS (with advanced PLUS extensions), PEXlib, GKS, IrisGL, and OpenGL.
   • Extensive networking capabilities via TCP/IP, Network File System (NFS) for file sharing, DECnet/OSI, and Network Application Support (NAS) for multi-vendor application integration.
   • Binary-compatible with the broader Alpha AXP family, supporting a range of application software like CAD, desktop productivity tools, and even an MS-DOS emulator (DEC SoftPC).

3. Graphics Options:

   • HX Graphics Option: 8-plane, accelerated 2D graphics and windowing operations using a Smart Frame Buffer ASIC.
   • Accelerated 3D Graphics Options (PXG+ and PXG Turbo+): TURBOchannel-based, configurable 8- or 24-plane (PXG+) or 96 raster plane (PXG Turbo+) options with double buffering and Z-buffer support, featuring hardware acceleration for 2D scan conversion and 3D geometry processing (via Geometry Engine and PixelStamp architecture).
   • Supports multiscreen configurations for HX options.
   • Performance is characterized using industry benchmarks like x11perf and Picture-Level Benchmarks (PLB).

4. Server Specifics (DEC 3000 Model 400S AXP):

   • Functions as a multi-user server, suitable for small businesses and distributed computing, serving as a disk file server, shared database host, peripheral host, network gateway, scientific computation host, and timesharing system.
   • Server performance is evaluated using AIM Suite Benchmarks (Milestone and Multiuser) and TPC Benchmarks (TPC-A, TPC-B) for transaction processing.

The document emphasizes the system's high performance due to the Alpha AXP 64-bit architecture and advanced hardware and software implementations, positioned as a computing solution designed for the 21st century.