The BSDs, SCO Await Intel's Nocona 64-Bit Xeon Servers

by Timothy Prickett Morgan

As expected, Intel this week rolled out the first of the 64-bit versions of the Xeon processors that it promised to deliver to the market in February. The "Nocona" variant of the Xeon DP processor will have the Extended Memory 64-bit Technology that was embedded into the "Prescott" Pentium 4 core upon which Nocona is based turned on. This summer, Nocona will appear in servers, and that is when things will get interesting for the BSD variants of Unix.

And next year, when The SCO Group rolls out 64-bit support for its OpenServer and UnixWare variants running on these new Xeon DP chips, as well as on the future "Potomac" Xeon MPs (for four-way and larger systems), customers who like SCO Unixes running on commodity X86 iron will finally have a 64-bit server platform from Intel that they can play with. Cheap 64-bit Intel iron for BSD and SCO Unixes has been a long time in coming, although Advanced Micro Devices has done its part by spurring Intel to stop trying to push Itanium and to actually get 64-bit Xeons out the door. (Incidentally, SCO OpenServer and UnixWare can run in 32-bit mode on the new Xeons and also on the Opterons; the BSD variants of Unix run in either 32- or 64-bit mode on the Opterons today.)

It is widely believed that Intel reversed engineered the X86-64 instruction set from the hybrid 32-bit/64-bit Opteron processors from AMD, and is launching the Noconas in workstations and soon in servers to try to blunt the attack that AMD has made on Intel's corporate computing turf.

Intel had promised back in February that it would ship the Nocona chips, which are built using a 90 nanometer chip process, before the end of the second quarter, and it is just squeaking by on that deadline as it gets the first chips and related "Tumwater" chipsets out the door for workstations on June 28. Back in February, Intel said that the Noconas would run at 3.2 GHz, have 1 MB of L3 cache, and will sport an 800 MHz frontside bus. The Noconas might be running tight up against their launch window, but Intel has been able to crank the clock speeds from 2.8 GHz through 3 GHz, 3.2 GHz, 3.4 GHz, and on up to 3.6 GHz in the workstation versions of the new Xeon DPs. The server versions of the chips should be around the same speed.

In addition to the 64-bit processing support (and the pipe going out to memory is only 64-bits wide, by the way), Nocona sports a lot of new features, including the SpeedStep power management technology that Intel developed for its Pentium M and Centrino mobile processors. SpeedStep varies the voltage and frequency of the processor, stepping it down as software is asking the processor to do less work, thereby eliminating some of the power consumption and heat exhaust that a regular Xeon chip has. This is particularly important in a chip like the Xeon, which has a lot of transistors and burns a lot of juice.

The Tumwater chipset for workstations, known as the E7525, supports 400MHz DDR2 memory as well, which consumes anywhere from 30 percent to 40 percent less energy than DDR1 memory running at 266 MHz or 333 MHz, respectively. According to Alan Priestley, strategic marketing manager for Intel's enterprise solutions in EMEA, the Nocona chip can step down from 3.6 GHz at 1.4 volts and dissipating 100 watts down to 2.8 GHz running at 1.2 volts and dissipating 70 watts. Other improvements in system design can reduce power consumption for a typical workstation, which eats anywhere from 300 watts to 400 watts, by around 28 percent, he says.

The Tumwater chipset and Nocona chips also enable the first Intel machines to support PCI Express, which offers 8 GB/sec of total bandwidth between the memory controller, graphics processor, and Nocona processor. For graphics, the PCI Express link will be comprised of the X16 16-lane bi-directional point-to-point bus, which will offer two times the bandwidth as AGP8X graphics subsystem in current Xeon workstations. The Tumwater chipset has an aggregate I/O bandwidth of 6.4 GB/sec, and supports up to 16 GB of main memory (two channels, four DIMMs per channel). Without using the 64-bit memory extensions or the X16 graphics, a top-of-the-line 3.6 GHz Nocona workstation benchmarked by Intel has run workstation applications 30 percent faster than the current 32-bit Xeons running at 3.2 GHz. This is roughly the same performance benefit that AMD has been saying that Opterons give over Xeons running 32-bit X86 applications.

The Tumwater chipset will cost $100 in 1,000-unit quantities. Prices for the Nocona chips will range from $209 for the 2.8 GHz chip to $455 for the 3.2 GHz version to $851 for the 3.6 GHz version. As is always the case with an new Intel chip, that faster 3.6 GHz part will be scarce as hen's teeth as the company ramps up production. Full volume shipments will probably be in swing by the middle to the end of the third quarter.

As for the server version of the Nocona chip and its associated "Lindenhurst" chipset, mum's the word. But the word on the street is that we can expect to see very similar configurations for servers sometime in the middle of summer. Nocona workstations and servers will obviously support X86 Unixes as well as Linux and Windows.