Alpha/Linux Wiki

Complete Alpha systems were sold by Digital, Compaq, HP, and others. Each has its own page, listed in the table below; the prototype Alpha Development Unit, which was never sold, has one too. Evaluation boards and OEM motherboards have their own pages under Motherboards, and which operating systems each system runs is on the Operating Systems page.

The kernel platforms, core logic, and the systems each platform covers are from the kernel configuration. ¹⁾ Codenames are from the kernel's system variation tables, ²⁾ the Alpha AXP System Reference Manual, ³⁾ and lists posted by Digital engineers. ^{4) 5)}

The firmware column gives the last SRM version released for the system, from Final versions, and whether it also has the ARC or AlphaBIOS firmware. The Linux column says whether current kernels support the system. "Linux 6.9 and earlier" marks systems whose processors Linux 6.10 dropped, and the AlphaServer 2100A and 2000A, whose platform it dropped. "Supported (21164A models); others Linux 6.9 and earlier" means that current kernels support only the system's EV56 (21164A) configurations, and that configurations with older processors ran up to Linux 6.9 (see Operating Systems). "Untested" means that current kernels contain support for the system but no one has reported booting one on it.

Since Linux 6.10, the kernel requires at least an EV56 (21164A) CPU; "the remaining EV5 based machines all support the slightly more modern EV56 generation as well." ⁶⁾ Systems still fitted with an original 21164 need a CPU upgrade to run current kernels; see Current Status. For the systems marked "Linux 6.9 and earlier", the newest maintained kernel is Linux 6.6, the last long-term release before 6.10; kernel.org projects its end of life for December 2027. ⁷⁾

The SRM console command show config lists the model name, firmware versions, processors, memory, and PCI and EISA devices. ⁸⁾ Under Linux, /proc/cpuinfo shows the system type and system variation from the HWRPB, which name the kernel platform and variation in the table above, and the console's platform string. ⁹⁾ For example, a GS320 reports "system type : Wildfire" and "platform string : AlphaServer GS320 6/731". ¹⁰⁾ The Digital Server "white box" systems report the negative of the real system type, which the kernel corrects. ¹¹⁾

A generic kernel runs on every supported system, while a kernel configured for a specific system is faster and smaller. ¹²⁾ A kernel built for one platform panics with "Unsupported system type" on any other. ¹³⁾ The alpha_mv= boot option forces a machine vector, for example -flags "alpha_mv=Rawhide". ¹⁴⁾

The Titan, Wildfire, and Marvel consoles occupy 8 MiB or more of memory, compared with 2 MiB on older systems, so the kernel must be linked to start above the console. ¹⁵⁾ A generic kernel built with CONFIG_ALPHA_LEGACY_START_ADDRESS, which the default configuration enables, is linked at the old address for boot loaders that hardcode it. Such a kernel leaves out Titan, Wildfire, and Marvel support entirely, so kernels for these systems must be built with the option off; see Kernel. ^{16) 17)}

• Dead battery: console settings are kept in memory backed by the motherboard's 3.3 V battery, so settings that do not survive a power cycle usually indicate that the battery has failed. ¹⁸⁾ The battery varies: the Personal Workstation uses a CR2032 coin cell, and when it dies the machine starts in AlphaBIOS instead of SRM. ^{19) 20)} On one system with a CR2032, a dead cell also reset the clock to 1 January 1995, and the console settings had to be entered again. ²¹⁾ Older boards such as the AXPpci 33 use a Dallas DS1287 clock module with a built-in battery, which can be replaced with a DS12887. ²²⁾
• Power supplies: aging power supplies fail, most often through their capacitors. The DS20L and CS20 supplies are particularly prone to failure, which shows as the front LED changing from flashing green to steady red. ²³⁾ The XP1000 and Personal Workstation use standard ATX supplies, of 350 W and 300 W, which are easy to replace. ²⁴⁾ Some server supplies are built for 200 to 240 V only: an ES45 "B" model reports every supply as failed on 120 V. ²⁵⁾
• Fans: the systems monitor their fans, and halt or shut down when one stops; the PC164 halts if its CPU fan stops, ²⁶⁾ and the DS10 and DS25 shut down on a fan failure. ^{27) 28)} A dead fan in a power supply should be replaced at once: on the CS20, "A working PSU with dead fan will die within hours." ²⁹⁾
• Mismatched CPUs: in multiprocessor systems, not every CPU module can be mixed with every other, even at the same speed. For the DS20 and DS20E, compatibility goes by module part number, and some revisions of the same speed cannot be combined; ³⁰⁾ on the ES40, pass 2.3 and pass 2.5 EV6 processors cannot be mixed. ³¹⁾ Use identical modules, with the same part number and revision, and check the system's configuration guide. A secondary CPU that fails to start shows in the kernel log as "SMP: Processor 1 failed to start". ³²⁾
• Chipset and board failures: a significant number of UP2000+ boards have chipsets that have failed through electromigration. ³³⁾
• Clock epoch: SRM and ARC store the time of year clock registers differently. ³⁴⁾ The kernel guesses the epoch from the year register, and the epoch= boot option overrides the guess. ³⁵⁾
• Memory: banks should be populated with identical DIMMs. ³⁶⁾ Systems with wider memory buses need more DIMMs per bank: pairs in the DS10, and sets of four in the XP1000 and DS20. ³⁷⁾
• Failed CPUs: a bad CPU in a multiprocessor system should be disabled with the SRM cpu_enabled variable, a bit mask with bit 0 for CPU 0. ^{38) 39)}
• Multiprocessor systems need SRM: MILO does not support multiprocessor systems. ⁴⁰⁾ See Boot Loaders.

For running a current distribution, a system needs an EV56 or later processor, an SRM console, and enough memory, and the 21264 systems are much faster than the 21164A ones. Other considerations are noise, power, and whether parts are available.

• DS10, DS15, XP1000: single-processor 21264 systems. The DS10 and DS15 are the most practical choice for a hobbyist. ⁴¹⁾ The XP1000 uses an ATX power supply, and draws between 300 and 500 W. ⁴²⁾
• DS20E, DS25, ES40, ES45: multiprocessor servers, faster but power-hungry: a DS20E or DS25 draws about 500 W at idle. ⁴³⁾ Some ES45 models need a 200 to 240 V supply.
• DS20L and CS20: compact but loud, ⁴⁴⁾ with unreliable power supplies. ⁴⁵⁾
• UP1000 and UP1100: limited to 768 MiB of single-channel SDRAM. The UP1500 has DDR memory and is better, but rare. The UP2000 and UP2000+ need an Extended ATX case and about 600 W. ^{46) 47)}
• Personal Workstation: a 21164A workstation, and a quiet one, ⁴⁸⁾ but early models have a DMA bug in their 64-bit PCI slots; see Other Hardware.
• EV56 servers: the AlphaServer 800 and 1000A, 1000, 1200, 4000, and 4100, and 2000 and 2100 still run current kernels when fitted with 21164A (EV56) processors, but are much slower than the 21264 systems.
• EV4, EV45, and EV5 systems run nothing newer than Linux 6.9, and so no current distribution kernel; NetBSD and OpenBSD still support them.

Whatever the system, a serial console, the last SRM version, and a new battery are the first steps; see Installation. Add-in cards known to work are listed under Other Hardware.

These notes apply to the XP1000, DS10, DS10L, and XP900, DS20 and DS20E, ES40, and DS20L and CS20. The Tsunami systems share the kernel's DP264 platform code: the DS20L and CS20 use its Shark variant, selected with CONFIG_ALPHA_SHARK, and the others use CONFIG_ALPHA_DP264, which also covers API's 264DP, UP2000, and UP2000+. ^{49) 50)}

• Later consoles for the DS10, DS20, ES40, and XP1000 present IDE disks as a separate device rather than through SCSI emulation. ⁵¹⁾
• The SRM console can use a VGA card on the second PCI bus. ⁵²⁾ Linux supports this with CONFIG_VGA_HOSE, for platforms that always have multiple PCI hoses. ⁵³⁾

• Model numbers: in a name such as AlphaServer 1000 4/233, the digit before the slash is the CPU generation and the number after it is the speed. On the AlphaServer 1000, 4/xxx denotes an EV4 CPU daughtercard, and 5/xxx an EV5-generation system, also called Mikasa Pinnacle or Primo. ⁵⁴⁾
• AlphaStation and AlphaServer names: the scheme is "AlphaMumble S G/M", in which S is a rough size class, G the chip generation, and M the clock speed in MHz. ⁵⁵⁾
• Personal Workstation a-series and au-series: the two differ only in the options offered. An "a" could be ordered with options supported only by Windows NT, and an "au" only with options supported by all three operating systems (Windows NT, Digital UNIX, and OpenVMS). ⁵⁶⁾
• Digital Server: the Digital Server 3300, 5300, and 7300 are Windows NT versions of the AlphaServer 800, 1200, and 4100. ^{57) 58)} The 3300 and 5300 run Linux and the BSDs without modification. ⁵⁹⁾ They can be switched to SRM from the AlphaBIOS setup menus. ⁶⁰⁾
• Codenames: the early systems were named after cars: Jensen, Morgan (never sold), Mustang (AlphaStation 200), Avanti (AlphaStation 400), Cabriolet, Miata, and Sable. ⁶¹⁾ The codenames were intended for internal use only. ⁶²⁾

The AlphaStation and AlphaServer names were introduced together on 3 November 1994, with eight systems: the AlphaStation 200 4/166, 200 4/233, and 400 4/233, the AlphaServer 1000 4/200, the AlphaServer 2000 4/200 and 2100 4/275, and the DEC 7000 Model 700. ⁶³⁾ The systems shared PCI with EISA or ISA as their I/O bus, and a choice of DEC OSF/1, OpenVMS, or Windows NT. ⁶⁴⁾

These documents cover the AlphaServer line as a whole; documents for a single system are on that system's page.