Altix 350

An early Altix 350
An early Altix 350

The SGI Altix 350, is a rack-mounted, mid range server sold by Silicon Graphics from 2005 to 2007. This system uses Itanium 2-based processors and while visually similar to the Origin 350, and sharing some ancillary parts, it is a clean break in design and runs RHEL and SLES Linux. The Altix 350 implements the IP57 processor, but follows the IP41 architecture from the earlier Altix 3000 systems. A system can include from 1 to 32 processors in up to 16 modules or bricks, with one or two NUMAlink routers connecting them. Configurations up to 8 modules can be organized in a ring topology without a router.


Each base module has four PCI slots across two PCI buses. The first CPU brick in a system has a single PCI slot holding an IO9 or IO10 BaseIO card with SCSI interfaces for two internal disks, an external SCSI port, audio I/O and a twisted pair Ethernet connection. The more rare IO10 is a SATA card.

The different configurations are:

  • Base Module
  • CMPX Expansion Module ("Cpu Memory Pci/pci-X")
  • CPU Expansion Module
  • NUMAlink 4 Router Module (often labeled "NL4R")

An Altix350 cannot be booted by itself without the presence of a BaseIO card. If a brick lacks it, one must be installed or otherwise the brick must be numalinked.


Each brick can take single or dual CPU configurations the same as the Prism. The CPUs are attached to the node board, thus a configuration upgrade requires removal of the entire node board.

CPU Configurations
CPU Cache Speeds (GHz)
1.5MB 1.0, 1.4
3MB 1.3, 1.4, 1.6
4MB 1.4, 1.5
6MB 1.5, 1.6
9MB 1.6


Like other first-generation Altix systems, the Altix 350 uses registered DDR DIMMs with ECC, rated at 266MHz or faster, which are commonly referred to as PC2100, PC2700, etc. Memory is organized in three banks of four DIMMs each, or twelve slots total, providing up to 24GB of RAM total per base module. DIMMs of 512MB, 1GB, and 2GB are officially supported; it is unclear as of this writing if 4GB parts will work.


The IO9 controller supports Ultra160 SCSI devices and includes an externally-accessible VHDCI port, while the IO10 controller supports SATA devices and includes a high density serial connector. Both controllers include a separate IDE interface to support optical drives.

Either IO controller provides one 1000baseT Ethernet interface. Three PCI-X slots can provide additional cards, such as network cards, SCSI cards, Firewire, extra audio and more. The BaseIO card must be installed in the bottom slot.

Two USB ports and PS/2 are provided. USB Mass storage is not supported for the SGI PROM and by IRIX.

NUMAlink is a high-speed low-latency switched fabric computer bus used as a shared memory computer cluster processor interconnection in Silicon Graphics computer systems. The Altix 350 leverages NUMALink heavily to link bricks together.

Multiple bricks are co-ordinated at startup time via an L2 Controller which communicates to the bricks via USB ports. The L2 Controller is an external PowerPC Linux unit with console, USB, modem and ethernet ports.

A system consists of up to sixteen CPU "bricks" (2 rackmount units high each) with up to two CPUs in each brick, giving a maximum of 32 CPUs. CPU bricks are connected together via NUMAlink4 cables going to one or two central NUMAlink Router (or NUMAlink Module) which is another 2U rackmounted unit.


The Altix 350 has a front bay for two 3.5" drives. It uses proprietary sleds for this purpose.

The Origin/Onyx 350, Prism, Altix 350, and Altix 450/4x00 all use the same drive carriers. These are standard parts used by a number of manufacturers, notably Intel's SC5200, SRSH4, SR1300/2300, and SR1400/2400 and Sun's v60x and v65x servers.

The units carry "Assy A65278-00x" on a sticker, where the "-00x" may end in any digit though "-005" seems common. This assembly number can be useful when searching for parts in the Internet. According to SR1300/SR2300 support documents at intel.com, the Intel accessory part number for the drive carrier is FXX2DRVCARBLK, UPC code "7 35858 14621 0" and "MM #" 835853. However note that there is some indication that Intel may recycle these accessory part numbers in the FXX- form between different models.

Hardware Problems

The main issue affecting these units is invalid serial numbers, which can be fixed using another brick, an L2 controller, or an L2 emulator called an L3 controller.

Operating System Support

The system can run Microsoft Windows up to Server 2008 R2 (Itanium Edition) and GNU/Linux RHEL and SLES up to versions 5 and 9 respectively.