This page covers the core logic used on the motherboards. Chipsets used only in Digital's and Compaq's own systems, such as Titan, Marvel, and Wildfire, are listed under System chipsets and described on the system pages.

The Linux code column names the file in arch/alpha/kernel that supports the chipset. The APECS and LCA files were removed with support for processors older than the EV56 (21164A) in Linux 6.10; ^{1) 2)} the CIA code remains for EV56 systems. The Current kernels column uses the same values as the Motherboards table.

The 21066 and 21066A integrate their memory and PCI controllers, so boards such as the EB66 and EB66+ need no separate chipset. Linux supported them with core_lca.c through Linux 6.9.

The kernel also has core logic support for chipsets that appear only in Digital's and Compaq's systems. Whether a system runs current kernels depends on its processor as well; see the Linux column of the Systems table.

The kernel configuration names the systems each platform covers, and builds the T2 code for Sable and the MCPCIA code for Rawhide. ³⁾ sys_sable.c covers the Sable, Sable-Gamma, and Lynx systems, and core_t2.c serves both Sable and Lynx, ^{4) 5)} core_mcpcia.c is the "code common to all MCbus-PCI Adaptor core logic chipsets", ⁶⁾ and core_marvel.c manages the IO7 chips of the EV7 systems. ⁷⁾ The Titan and Wildfire code is in core_titan.c and core_wildfire.c. ^{8) 9)}

The 21071 and 21072 are "two configurations of a core logic chip set for the DECchip 21064 family", providing a 32-bit PCI interface, cache and memory control, and the data paths between them. Digital shipped them with the EB64+ evaluation kit, "an example PC mother board" that also served as the debug platform for the chips, with the aim of letting designers build uniprocessor Alpha systems "with minimal design and engineering effort". ¹⁰⁾

The 21171 (CIA) is the core logic of the EB164 and of EV5 systems such as the AlphaStation 500 and 600 (Alcor). Linux supports it in core_cia.c, which also handles the 21172 and 21174. ¹¹⁾

The 21172 (CIA-2) is the core logic of the AlphaPC 164. Although it was intended to allow byte and word access to I/O space, this never worked, so Linux uses sparse I/O addressing on it as on the 21171. ¹²⁾

Early 21174 (Pyxis) parts have an erratum affecting DMA that crosses a page boundary when the scatter-gather hardware is in use, ¹³⁾ which operating systems must work around. NetBSD prints a warning when it detects a pass 1 Pyxis. ¹⁴⁾ On the Personal Workstation (Miata), the PCI-to-PCI bridge in front of the 32-bit slots masks the bug; see Other Hardware for the 64-bit slots, which are not behind it.

Pyxis was also the first Alpha core logic on which byte and word access to I/O space worked, and Linux enables it on every Pyxis system; ¹⁵⁾ see Byte and Word Access.

The VLSI Technology Polaris system controller is used only on the AlphaPC 164RX. It supports only 32-bit PCI. ¹⁶⁾ Linux supports it in core_polaris.c. ¹⁷⁾

The 21272 (Tsunami, and the later Typhoon) is the core logic of the 21264 motherboards and of the AlphaServer DS10, DS20, and ES40 families. Linux supports it in core_tsunami.c. ¹⁸⁾

The AMD-751 (Irongate) is an Athlon system controller, used with the 21264 on the UP1000 and UP1100. Linux supports it, and the AMD-761, in core_irongate.c. ¹⁹⁾

The AMD-761 is an Athlon system controller with a DDR SDRAM memory interface, ²⁰⁾ used on the UP1500. core_irongate.c supports it and tells it apart from the AMD-751 by device ID, since the two keep their ECC status in different registers. ²¹⁾