UP2000 Motherboard — Dual-Processor Alpha 21264 Server Board
The UP2000 was Alpha Processor, Inc.'s dual-processor server board: two Alpha 21264 processors on a Tsunami-class chipset with wide memory, 64-bit PCI and ECC protection. It gave integrators a way to build serious Alpha servers and cluster nodes without buying a complete proprietary system.
From desktop to server
API's single-processor UP1000 borrowed AMD's Irongate desktop chipset to keep costs low, and that choice came with limits: a 32-bit PCI bus, a single processor and a memory ceiling below one gigabyte. For server, database and technical computing buyers, those limits were deal-breakers. The UP2000 was designed to remove them.
Instead of a PC chipset, the UP2000 is built around the Tsunami family of Alpha system logic that Digital developed for its own 21264 servers and workstations, the same class of chipset found in machines such as the AlphaServer DS20. Tsunami was designed from the start for multiprocessor Alpha systems, with a crossbar-style memory architecture and multiple independent PCI buses. Putting it on an open, merchant-market board was a significant step: integrators could now build systems with server-class Alpha plumbing using their own enclosures, drives and networking.
Architecture
The board carries two Slot B connectors, each accepting an API Alpha 21264 module with its own backside L2 cache. Each processor has a dedicated point-to-point EV6 link to the chipset rather than sharing a single front-side bus, so adding the second CPU does not halve the available processor bandwidth, a notable contrast with the shared-bus x86 servers of the day.
The Tsunami-class logic is split into several chips: a control chip that arbitrates processor and memory traffic, data-path chips that move memory data at high width, and PCI interface chips that provide two separate 64-bit PCI buses. Splitting I/O across two buses let a system run, for example, a high-speed cluster interconnect on one bus and storage controllers on the other without them competing for the same bandwidth.
Main characteristics
| Feature | UP2000 |
|---|---|
| Processors | One or two Alpha 21264 (EV6) on Slot B modules |
| Clock speeds | Roughly 600-667 MHz on the original board; faster 21264A parts on the later UP2000+ |
| L2 cache | Backside cache per module, typically 4 MB |
| Chipset | Tsunami-class Alpha system logic (control, data-path and PCI chips) |
| Processor interconnect | Dedicated EV6 point-to-point link per CPU |
| Memory | Registered ECC SDRAM DIMMs, wide memory data path, capacity in the multi-gigabyte range |
| Expansion | Two independent 64-bit PCI buses plus 32-bit slots |
| Integrated I/O | SCSI and standard legacy peripherals (configuration dependent) |
| Form factor | Oversized, extended-ATX-style server board |
| Firmware | Alpha SRM console (with AlphaBIOS heritage) |
| Recommended enclosure | API PowerRAC Chassis 320 (3U rackmount) |
The larger board size was a direct consequence of the chipset: Tsunami is a multi-chip design and needs room for its data-path parts and wide memory banks. That made the UP2000 harder to fit into generic tower cases, which is one reason API designed a dedicated rackmount enclosure for it.
Target workloads
API aimed the UP2000 at buyers who needed a lot of floating-point performance, memory bandwidth or I/O in a single node:
- Compute clusters — dual-CPU nodes for Beowulf-style Linux clusters in universities, government labs and engineering firms.
- Render farms — rackmounted nodes for film and visualisation studios running CPU-bound renderers.
- Internet infrastructure — web, mail and application servers for ISPs and hosting providers that wanted 64-bit headroom.
- Database and technical servers — memory-hungry applications that benefited from large address spaces and ECC-protected RAM.
Clusters were the market where the UP2000 made the strongest case. A 21264 delivered excellent double-precision throughput, and pairing two per board with 64-bit PCI for Myrinet or similar interconnects produced nodes that compared well with far more expensive proprietary supercomputing hardware. Several academic Alpha clusters of the era were built from API boards.
Operating system and software support
As with the rest of API's line, Linux was the lead operating system. The Alpha Linux kernel gained SMP support for Tsunami-based systems, and the major Alpha distributions of the time, including Red Hat, SuSE and Debian, could be installed on the board. Compaq's Alpha compilers and math libraries for Linux gave scientific users a substantial boost over plain GCC, and they were a standard part of most serious UP2000 cluster builds.
Because the UP2000 shares its chipset family with Compaq's own Tsunami-based systems, it sits closer to the "official" Alpha world than the UP1000 did. Even so, Tru64 UNIX was licensed and validated primarily for Compaq hardware, so running it on an API board was not a mainstream, fully supported configuration; buyers who needed certified Tru64 generally stayed with AlphaServers. Windows NT for Alpha had been cancelled in 1999, so it was not a meaningful target for this board. The BSD family, particularly NetBSD, supported Tsunami-class platforms and could be brought up by experienced users.
The UP2000+ variant
API later offered a revised board usually referred to as the UP2000+. As far as surviving documentation indicates, the main change was support for the faster, die-shrunk Alpha 21264A modules, allowing higher clock speeds than the original board, along with incremental updates to firmware and components. Details differ between sources, and it is best to treat the UP2000+ as an evolutionary refresh rather than a new platform. The same technology also fed into API's later high-density server work.
Positioning within the API product line
The UP2000 sat at the top of API's board range, above the single-processor UP1000 and UP1100. It was usually sold alongside the PowerRAC Chassis 320, a 3U rackmount enclosure built specifically for it, and the combination formed the basis of many integrator-built Alpha servers. Against Compaq's DS20, the UP2000 offered similar core architecture with more freedom over enclosures and components, at the cost of the vendor-certified operating system and service stack.
For company background see the corporate section.