Intel MPS-compatible hardware



This page is for references to manfacturers and machines supporting the Intel MultiProcessor Specification. I believe all these machines will run Windows NT and possibly OS/2 SMP, for example, but I'm most interested in compatibility with the various SMP versions of the free OSes.

To my knowledge, all Pentium Pro SMP systems should work perfectly fine with my startup code, which is already in Linux-SMP. It is known to work for many Pentium systems, but there has been at least one system which the user claimed it failed on (an ALR Revolution Q-SMP dual-Pentium), though I can't get into contact with him now to try to debug it.

DISCLAIMER!! This is not any kind of "official" guide. Any of these entries may be inaccurate, especially those I don't have links directly to. For those, I simply wrote what I thought was the case. If you need to rely on anything, go to the manfacturer first! In the interest of accuracy anyway... if you have additions, comments, or corrections about various kinds of hardware, please e-mail me with relevant details. Comments about compatibility are also welcome!

Categories of Hardware


The low-end machines that can be bought are generally a lot like a normal PC board, with a single L2 cache, normal PC memory, and standard I/O subsystem (with a single ISA/EISA and PCI/VLB bus). The motherboard has a standard form-factor and the whole thing looks like a normal PC.

The dual-Pentium motherboards fall into this category. If it is called a "dual-Pentium", then the description above is pretty accurate. Compared to other SMP systems, they are not stellar performers. The main attractive point is the fact that the price difference from a standard PC system is very small, usually a few hundred U.S. dollars plus the cost of the second CPU.

NOTE on Pentium Pro SMP machines: Since each Pentium Pro has it's own L2 cache integrated into the CPU package, even the lowest-end Pentium Pro SMP box will have a separate L2 cache per CPU, which greatly improves the performance of the whole system.


The mid-range machines are usually high-end desktops and low-end servers.

The hardware configuration varies, as each CPU generally will have it's own L2 cache, and may or may not have interleaved memory. If it comes as a system, the rest of the hardware is pretty high-quality.

NOTE: OK, so I'm biased... but the main difference between a "mid-range" and "high-end" machine is all the "high-availability" construction and hardware put into it. IMHO as high-performance multi-CPU Pentium Pro motherboards become available, people will be able to put together high-performance systems without the (currently) enormous price-differential in going from a 2-CPU-capable systme with 1 PCI bus and a wimpy memory subsystem to anything notably better. We'll see if this really happens, though... (I sure hope it does).


These beasts are generally used as high-end file and/or compute servers. They are generally much more expensive, but of much higher quality construction and designed for very high performance.

Par for the course on these systems are:

NOTE: Rumor has it that many of the vendors currently offerring high-end Pentium multiprocessors which look like the Intel Xtended Xpress boxes will soon be offerring high-end Pentium Pro multiprocessors which look like the Intel Alder boxes. I'm mainly maintaining links to web pages, and few currently have such links. If people are interested, they should contact the various companies sales offices and ask directly.

Manufacturers and Systems

A Caveat Emptor Warning: For high-performance options such as highly interleaved memory (4-way vs. 2-way or no interleaving), multiple PCI buses, etc... be warned that most of these are sales blurbs, so if it isn't explicitly listed, don't presume the machine has the feature! Call and nail down a sales or technical representative on the topic!

NOTE on pricing: Motherboards will almost always be cheaper than systems, and the "servers" will be VERY pricy. In general, by far the cheapest way to put together a fast SMP system is to assemble it yourself from a motherboard. It really comes down to if you want all the extra hardware (like hot-plug SCSI, special power-supplies, huge cases and lots of cooling design) and sevice that comes with the expensive boxes.

Intel Server Architectures

I don't know if any of these systems can be bought directly from Intel as an end-user customer, but I believe they serve as internal testbeds, benchmark platforms, technology demonstrations, and sometimes OEM boxes.

There are no web pages for these machines, but I feel it is relevant to mention what I know about them as I believe they are the architectural basis for many high-performance SMP x86 boxes. This information may be either inaccurate or out-of-date, but is meant to describe the approximate class of machines I'm working with.

Intel Xpress

1-2 CPU Pentium 60, 66, 90, 100. I don't know much about the other stats of this machine, but I think it has 2-way interleaved memory, an EISA bus (no PCI slots), and the standard set of integrated I/O (IDE, 2 serial, 1 parallel) plus an SVGA with a Western Digital chipset.

Intel Xtended Xpress

This machine is known to work with Linux-SMP.

Intel Alder

This machine is known to work with Linux-SMP.

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