Intel Crams Two Half-Size Motherboards into a Chassis

Published: November 14, 2006

by Timothy Prickett Morgan

With supercomputing, three of the most important factors in determining the performance of systems are the density of the computing infrastructure, the power it consumes, and money. This week, Intel is announcing two new half-size motherboards aimed at supercomputing customers who want low-frills compute nodes and who want to cram even more systems in a rack than they can today.

Intel is making its new server board announcements to coincide with the launch of the "Clovertown" quad-core Xeon 5300 processors, which launch today, and the SuperComputing 2006 trade show in Tampa, Florida.

Intel has come a long way when it comes to compute density, as have other chip makers. A decade ago, Intel's ASCI Red supercomputer had 9,000 Pentium Pro processors, took up 1,500 square feet of space, and consumed 800 kilowatts to deliver about 1.8 teraflops of number-crunching power. With the Clovertown chips launched this week, Intel says that it can do the same work in 16 square feet of space--nearly a factor of 100 better--and use less than 10 kilowatts--a factor of 80 improvement. But, you are only as good in the supercomputing business as the improvements you can bring to bear now.

And so, Intel has created the "Port Townsend" S3000PT motherboard, which will use a variant of the Clovertown chip called the "Kentsfield," which is designed for single-socket desktops, workstations, and servers but which delivers four processing cores. By using the single-socket Kentsfield, which will be rebranded as the Xeon 3200 when it ships early next year, each socket on the board has its own dedicated memory, I/O, and interconnect to the cluster, and moreover, the chip doesn't get bogged down with the overhead of cache coherency between multiple processor sockets. On many workloads, a single-socket, quad-core board will deliver better performance than a two-socket server with dual-core processors--particularly if that single socket has its own interconnect link and doesn't have to share it with another socket. And, being a single-socket processor, the Xeon 3200s are cheaper and so are the boards that use them.

The SP3000PT board is 5.9 inches wide by 13 inches deep, and two of these boards can fit side by side in a standard rack-mounted server chassis. The board has one I/O slot, which are intended for interconnection fabric only (such as InfiniBand), two Gigabit Ethernet ports if you want to use cheaper switching, and four 667 MHz DDR2 main memory slots. That comes to a total of 16 GB of main memory using 4 GB DIMMs, but considering how expensive those are, most HPC centers would opt for the much cheaper 2 GB DIMMs and max out at 8 GB for four cores. The board also has four SATA ports for disks. In single-unit quantities, Intel is charging $210 for the motherboard, not including the InfiniBand card.

Ciara Technologies puts four of these boards and four Kentsfield Xeon 3200 chips in a personal cluster--rather than a personal computer--that sells for under $12,000 and that offers 340 gigaflops of computing power. It is only slightly larger than a PC and comes in a deskside form factor.

Intel, server maker Supermicro, and interconnect specialist Mellanox have teamed up to create yet another variant on this theme, called the "Atoka" motherboard, which is also a halfsie board like the Port Townsend one created by Intel. Only the Atoka board is based on the dual-core "Woodcrest" Xeon 5100 and Clovertown Xeon 5300 processors, which means it has two sockets on the half-board rather than just one.

The Atoka board will only be available through Supermicro, and its exact specifications have not been revealed yet. But according to Intel, the board measures 5.9 inches by 16 inches, which means you can cram two into a large rack server side by side. Each board has two Gigabit Ethernet and one InfiniBand port right on the motherboard--the latter being the first time InfiniBand has been moved down to the board in the server racket. Others are surely working on it. IBM is said to be putting InfiniBand native on the boards in its Power6 machines, and it is hard to imagine that Sun Microsystems is not doing the same for its own Opteron-based boxes.