• Specification Changes are modifications to the current published specifications. These changes will be incorporated in the next release of the specifications.
• S-Specs are exceptions to the published specifications, and apply only to the units assembled under the S-spec.
• Errata are design defects or errors. Errata may cause the Pentium® II Xeon® processor's behavior to deviate from published specifications. Hardware and software designed to be used with any given stepping must assume that all errata documented for that stepping are present on all devices.
• Specification Clarifications describe a specification in greater detail or further highlight a specification's impact to a complex design situation. These clarifications will be incorporated in the next release of the specifications.
• Documentation Changes include typos, errors, or omissions from the current published specifications. These changes will be incorporated in the next release of the specifications.

• Introduction
  
• Thermal Management
  
• Integrated Heatsink
  
• System Airflow
  
• Thermal Testing (System Checkout)
  
• Testing Hints
  

Introduction

This document is written for professional system integrators building PCs from industry-accepted motherboards, chassis, and peripherals. It provides information and recommendations for thermal management in systems using boxed Intel® Pentium® II Xeon™ processors.

It is assumed that the reader has a general knowledge of and experience with workstation and server operation, integration, and thermal management.

Thermal Management

All systems using Pentium II Xeon processors require thermal management. In this case, "thermal management" includes two major elements: (1) a heatsink properly mounted to the processor and (2) effective airflow through the system chassis. The ultimate goal of thermal management is to keep the processor at or below its maximum operating temperature. Table 1 shows the maximum operating temperatures of specific Pentium II Xeon processors. The maximum operating temperature is measured at the center of the surface of the processor's thermal plate and varies depending on the particular frequency and stepping of the processor.

Proper thermal management is achieved when heat is transferred from the processor to the system air, which is then vented out of the system. Boxed Pentium II Xeon processors are shipped with an attached passive heatsink, which requires system airflow to effectively transfer processor heat to the system air. It is the responsibility of the system integrator to ensure adequate system airflow.

This document makes recommendations for achieving good system airflow.

Integrated Heatsink

Boxed Pentium II Xeon processors are shipped with an attached heatsink. The processor and heatsink should be used following the directions contained within the boxed Pentium II Xeon processor installation notes. Figure 1 shows the processor and heatsink.

Figure 1. Boxed Pentium® II Xeon® Processor and Heatsink

The heatsink that ships with the boxed Pentium II Xeon processor has already been securely attached to the processor. A small amount of thermal grease (already applied) provides effective heat transfer from the processor to the heatsink. The heatsink requires sufficient system airflow in order to keep the processor cool.

Some retention mechanisms supplied with Pentium II Xeon processor based motherboards provide locations for mounting small fans that draw air through the heatsink's cooling fins. Figure 2 shows an example of a second Pentium II Xeon processor being installed in a dual retention mechanism (DRM). In this example, two small fans are installed in the DRM. The fans ensure airflow over the cooling fins of the second processor's heatsink. Note that, unlike the second processor, the first processor has no fans directly drawing air across its heatsink. The system must provide adequate airflow to cool the first processor, which is without its own fan. The DRM fans must draw hot air from both processors out of the chassis. Check with your motherboard manufacturer for details about retention mechanisms and cooling solutions.

Figure 2. Boxed Pentium® II Xeon™ Processor Being Installed into Dual Retention Mechanism (DRM)

System Airflow

System airflow is determined by:

• Chassis design
• Chassis size
• Location of chassis air intake and exhaust vents
• Power supply fan capacity and venting
• Location of processor(s) slots
• Placement of add-in cards and cables

Integrators use two basic motherboard-chassis-power supply form factors: ATX and the older Baby AT form factor. Due to cooling and voltage considerations, Intel recommends the use of ATX form factor motherboards and chassis for the boxed Pentium II Xeon processor.

The ATX form factor simplifies assembly and upgrading of PCs, while improving the consistency of airflow to the processor. On ATX motherboards, the processor slot is located close to the power supply, rather than to the front panel of the chassis. This increases air circulation flowing directly across the processor. System component heat is dissipated into the chassis environment that is exhausted out while fresh air is brought in. Figure 3 below shows an example of typical airflow through an ATX system. Intel recommends ATX chassis that comply with the ATX 2.01 specification found on the ATX Web site. The ATX Web site also lists chassis manufacturers.

Figure 3. System Airflow through ATX Tower Chassis (side view)

The following is a list of guidelines to be used when integrating a system.

• Provide sufficient air vents: Systems must have adequate air vents in addition to a fan. Chassis vents must be fully functional. System builders should be careful not to select chassis that contain cosmetic vents only. Proper location of vents results in a good stream of air flowing over the processor.

• Power supply air flow direction: It is important to choose a power supply with a fan that moves air in the proper direction. For most ATX systems, the power supply acts as an intake fan, pushing air out of the system.

• Power supply fan strength: For some chassis that are running too warm, changing to a power supply with a stronger fan can greatly improve airflow.

• System fan--should it be used? Some chassis may contain a system fan to assist airflow. A system fan is typically used with passive heatsinks. In some situations, a system fan greatly improves system cooling. Thermal testing both with a system fan and without the fan will reveal which configuration is best for a specific chassis.

• System fan airflow direction: When using a system fan, ensure that it moves air in the same direction as the overall system airflow. A system fan in an ATX system should act as an exhaust fan, moving additional system air out through the exhaust vents in the chassis.

• Protect Against Hot Spots: A system may have a strong airflow, but still contain "hot spots." Hot spots are areas within the chassis that are significantly warmer than the rest of the chassis air. Such areas can be created by improper positioning of the exhaust fan, adapter cards, cables, or chassis brackets and subassemblies blocking the airflow within the system. To avoid hot spots, place exhaust fans as needed, reposition full-length adapter cards or use half-length cards, re-route and tie cables, and ensure space is provided around and over the processor.

Differences in motherboards, power supplies, add-in peripherals, and chassis all affect the operating temperature of systems and the processors that run them. Thermal testing is highly recommended when choosing a new supplier for motherboards or chassis, or when starting to use new products. Thermal testing can determine if a specific chassis-power supply-motherboard configuration provides adequate airflow for boxed Pentium II Xeon processors. To begin determining the best thermal solution for your Pentium II Xeon processor based systems, contact your motherboard vendor for chassis and fan configuration recommendations.

Testing Hints

Use the following hints to reduce the need for unnecessary thermal testing.

1. When testing a system that supports more than one processor speed, test using the processor(s) that generates the most power. Processors that dissipate the most power will generate the most heat. By testing the warmest processor supported by the motherboard you can avoid additional testing with processors that generate less heat with the same motherboard and chassis configuration.

   Power dissipation varies with processor speed and silicon stepping. To ensure selection of the appropriate processor for your system thermal testing, refer to Table 1 for power dissipation numbers for boxed Pentium II Xeon processors. Boxed Pentium II Xeon processors are marked with a 5-digit test specification number, usually beginning with the letter S. Test specification numbers for a particular stepping of Pentium II Xeon processor can be found in the Pentium® II Xeon® Processor Specification Update, Order No. 243776.
   
   Table 1. Boxed Pentium® II Xeon® Processor Information

   Processor Core Speed (MHz) and L2 Cache Size Boxed Pentium® II Xeon® Processor Stepping Maximum Thermal Plate Temp (°C) Power Dissipation (W) 400/512KB B0/B1 75 30.8 400/1MB B0/B1 75 38.1 450/512KB B1 75 34.5 450/1 MB B1 75 42.8 450/2 MB B1 75 46.7

2. Thermal checkout with a new motherboard is not necessary if all of the following conditions are met:
   • The new motherboard is used with a previously tested chassis that worked with a similar motherboard
   • The previous test showed the configuration to provide adequate airflow
   • The processor is located in approximately the same place on both motherboards
   • A processor with the same or lower power dissipation will be used on the new motherboard

3. Most systems are upgraded (additional RAM, adapter cards, drives, etc.) sometime during their life. Integrators should test systems with some expansion cards installed in order to simulate a system that has been upgraded. A thermal management solution that works well in a system that is heavily loaded does not need to be re-tested for lightly loaded configurations.

The Pentium II Xeon processor at 400 MHz is available in 512K and 1 MB L2 cache options, and the Pentium II Xeon processor at 450 MHz is available in 512K, 1 MB, and 2 MB L2 cache options.

The Pentium II Xeon processor improves upon the Pentium Pro processor by adding MMX™ technology for 3-D compute-intensive applications, and by utilizing the S.E.C. (Single Edge Contact) cartridge package technology first introduced on the Pentium II processor.

Like the Pentium Pro processor, level 2 cache communication occurs at the full processor core speed.

A significant feature of the Pentium II Xeon processor, from a system perspective, is the built-in direct multiprocessing support. The Pentium II Xeon processor supports both uniprocessor and multiprocessor implementations with up to four processors on each local processor bus, or system bus.

The Pentium II Xeon processor system bus operates using GTL+ signaling levels with a new type of buffer utilizing active negation and multiple termination. This new bus logic is called Assisted Gunning Transistor Logic, or AGTL+.

Product Overview

• Power and performance for mid-range and higher servers and workstations.
• Available at operating frequencies of 450 MHz or 400 MHz
• 32KB (16KB data /16KB instruction) non-blocking, Level One (L1) cache provides fast access to heavily used data
• Dual Independent Bus (D.I.B.) architecture increases performance and provides more data to the processor core
• 100 MHz system bus speeds data transfer between the processor and the system
• 400 MHz offers 1 MB and 512 KB L2 cache options. 450 MHz offers 2 MB, 1 MB, and 512 KB L2 cache options.
• Level 2 cache bus operating at same speed as processor core provides new level of peak bandwidth to the processor
• Cacheable address space up to 64GB
• "Glueless" multiprocessing support for up to four processors
• Supports 8-way and beyond systems through other clustering technologies
• Intel® Extended Server Memory Architecture--expanded 36-bit memory support which allows operating systems and applications to utilize memory greater than 4 Gbytes
• Thermal sensor allows system to actively manage thermal conditions
• Error Checking and Correction (ECC) to maintain the integrity of mission-critical data
• Functional Redundancy Checking (FRC) to confirm processing integrity
• System Management Bus (SMBus) for efficient communications between the processor thermal sensor, processor-specific PIROM, OEM-writable EEPROM and the rest of the system

For more information, refer to the Intel Pentium II Xeon processor datasheet.

Intel Corporation
2200 Mission College Blvd.
P.O. Box 58119
Santa Clara, CA 95052-8119
USA

Global Trade Department
e-mail inquiries to: ctp.determinations@intel.com

Following are the Gigaflops (GFLOPS), Composite Theoretical Performance (CTP), and Adjusted Peak Performance (APP) values for Intel’s 32-bit and 64-bit processors. All Intel® 8-bit and 16-bit processors and microcontrollers with a clock speed exceeding 25 MHz are 3A991, with the exception of those encapsulated in military packages that have been tested to the Mil-883C temperature specifications. All Intel 8-bit and 16-bit processors and microcontrollers with a clock speed of 25 MHz or less are EAR99.

On November 5, 2007, the United States Department of Commerce’s Bureau of Industry and Security (BIS) published amendments to the Export Administration Regulations 15 CFR, which resulted in the inclusion of the December 2006 Wassenaar Arrangement Plenary Agreement Implementation.

The amendments introduced a new metric, Gigaflops (GFLOPS), to measure processor performance for export purposes. BIS no longer requires exporters to determine the CTP. However, CTP values will still be provided for those customers located in countries where the CTP is still required as a measurement of processor performance for export compliance purposes.

CTP calculations are based upon a modified formula resulting from Wassenaar negotiations on December 21, 1993, and published in the United States Department of Commerce Export Administration Regulations 15 CFR 774 (Advisory Note 4 for Category 4), and are stated in Millions of Theoretical Operations Per Second (MTOPS).

APP calculations are based on the formula published in the United States Department of Commerce Export Administration Regulations 71 CFR 20876, and are stated in Weighted Teraflops (WT).

All GFLOPS, CTP and APP calculations contained herein were based on specifications taken from Intel datasheets and are subject to change without notice. Intel makes no representation or warranty as to the accuracy or reliability of such specifications. THESE CALCULATIONS ARE PROVIDED "AS IS" WITH NO WARRANTIES WHATSOEVER, INCLUDING ANY WARRANTY OF MERCHANTABILITY, NONINFRINGEMENT, FITNESS FOR ANY PARTICULAR PURPOSE OR ANY WARRANTY OTHERWISE ARISING OUT OF ANY PROPOSAL, SPECIFICATION OR SAMPLE. Intel disclaims all liability, including liability for infringement of any proprietary rights, relating to use of information in these calculations. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted herein.

Version 7.2

The bootable version of the Intel® Processor Frequency ID Utility is available in .exe format. This download does not work in DOS-emulation windows, as found in operating systems such as Linux*. Since this version is bootable, it does not depend on any specific operating system (OS independent).

See the Installation Guide for detailed instructions on how to use this utility.

Which Utility Should I Use?
For Intel® Pentium® III processors, and processors manufactured before the Intel® Pentium® III processor, use the Intel® Processor Frequency ID Utility.

Version 7.2

The utility is available for download in a self-installing .msi file format.

• Supported Processors
• Supported Operating Systems

• Proper Intel® processor brand identification
• Processor and system bus expected frequencies
• Processor and system bus reported frequencies
• Accompanying this information is a message informing the user whether the processor is operating at its expected frequency
• Which processor was tested in a multiprocessor system, and total number of processors (Windows* XP, and Windows* 2000 only)

The CPUID Utility for Windows* is incorporated into the Intel® Processor Frequency ID Utility.

Use the CPUID Data Screen of the utility to identify Pentium® processors and higher.

• Windows 98* SE
• Windows 2000* Professional, Server, Advanced Server
• Windows Me*
• Windows XP*

This utility is designed to identify current Intel® Processors and technologies, and enables you to run and save a processor ID report. The utility also features a frequency test to make sure that the processor is working at the tested and rated speed.

The Intel® Processor Identification Utility video walks you through download to installation, and provides an overview of the most common technologies supported by the processor.

The latest version of Intel® Processor Identification Utility is available for download in a self-installing .msi file format.

The installation manuals and flyers for boxed processors are now available in 11 languages: English, Traditional Chinese, Simplified Chinese, Korean, French, Italian, German, Spanish, Portuguese, Russian, and Japanese.

	Installation Flyer - English - PDF
	File Name: P2XPFLY1.PDF Size: 5120 bytes Date: 04/15/99

	Installation Flyer - All Languages - EXE
	File Name: P2XPFLYA.EXE Size: 1287168 bytes Date: 04/15/99

• Pentium II Xeon Processor Features
• Boxed Pentium II Xeon Processor Contents
• Motherboard Selection
• Chassis Selection
• Processor Connector Requirements
• Voltage Requirements
• Thermal Management Considerations
• BIOS Considerations
• Dual and Multi-Processor System Considerations
• How to Match Processor Steppings
• Mixing Processor Steppings and Speeds

• Up to four processors using "glueless" multiprocessing capabilities
• Eight-way and above systems using clustering technologies like NUMA and VI architecture
• Greater than 4 GB of memory using expanded 36-bit addressing

• 0.25 micron P6 microarchitecture core operating at 450 MHz and 400 MHz
• Dynamic Execution
• 400 MHZ offers 1 MB or 512 KB L2 cache options.
• 450 MHZ offers 2 MB, 1 MB, or 512 KB L2 cache options.
• L2 cache bus operating at the same speed as the processor core
• New system management features via the System Management Bus (SMBus)

• 450 MHz processor with 2 MB, 1 MB, or 512 KB L2 cache or 400 MHz processor with 512 KB or 1MB L2 cache
• Attached Passive Heatsink
• Installation Manual
• Certificate of Authenticity
• Intel Inside® Logo Sticker
• 3-year Limited Warranty

1. Ship multiprocessor systems with all processor slots populated to ensure that processor speeds, steppings, and L2 cache sizes are the same. When partially populated systems are shipped, customers attempting to install additional processors may have difficulty locating them with the same stepping or cache sizes. In these cases, they may have to replace the original processor to obtain a system with processors of the same stepping.
   
   
2. Make sure that the correct motherboard BIOS is loaded into both processors. Contact your motherboard vendor if you have any questions on BIOS upgrades.
   
   
3. If a system is shipped without all processors installed, test the system first with all processor slots populated. This will demonstrate whether the motherboard supports multiprocessor operation. You should also provide these customers with speed and stepping information for the original processor. This will ensure they understand the importance of having processors of the same speed, stepping, and cache size. It also warns them of the risk of having to replace the original processor in the future if earlier stepping processors are not available.
   
   
4. If a system is shipped without all processors, install the operating system with all processors installed. Some operating systems will install different kernel versions, depending on the number of processors present. Once the operating system has been installed the remaining processors can be removed before system shipment. This alleviates the need to reinstall the operating system if more processors are added later. Make sure to populate all open processor connectors with appropriate termination cards which should have been supplied with your motherboard.
   
   
5. Integrators thinking about mixing processor steppings within a multi-processor system should first read Mixing Processor Steppings and Speeds for an overview of the issues involved.

• In mixed stepping configurations, all processors must be run at an identical frequency and must have the same L2 cache sizes
  
  
• The workarounds for various errata must take all processors into account. Errata for the Pentium II Xeon processor are published in the Pentium® II Xeon® Processor Specification Update.
  
  
• Errata for all processor steppings present in a system will affect that system, unless worked around.
  
  
• Some operating systems may not support full functionality when processors with mixed steppings are present. Check with your operating system vendor for details.
  
  Due to the variety of motherboard vendors in the market and the number of system BIOS revisions, some system-level issues may occur that lie outside the realm of any mixed stepping evaluation performed by Intel. Recommendations for shipping systems that mix Pentium II Xeon processor steppings are as follows:
  
  
• Choose a motherboard vendor with a history of quality and dual and multiprocessor experience to minimize potential system-level issues
  
  
• Contact your motherboard vendor for information on mixed stepping validation performed on your particular dual or multiprocessor motherboard
  
  
• Make sure that the motherboard’s BIOS will support all processor steppings. As indicated in BIOS Considerations above, motherboard vendors should be able to supply information about the steppings of the Pentium II Xeon processor supported by the BIOS on a specific motherboard.
  
  
• Refer to the Pentium® II Xeon® Processor Specification Update for information on processor errata, their workarounds and potential performance issues before integrating dual and multiprocessor systems. The specification update (order number: 243776-xxx) can be obtained from Intel literature at 1-800-548-4725. The order number changes with each specification update; the -xxx numbers grow larger with each revision. Choose the highest revision number to receive the latest update.

Information about mixing processors of different speeds can be found in the Pentium® II Xeon® processor at 400 and 450 MHz Datasheet.

Additional information related to stepping, voltage and packaging of each specific Pentium II Xeon processor can be found in the Pentium® II Xeon® Product Specifications and Comparisons.

The following older processor families are no longer supported through interactive support such as phone, e-mail, or chat.

Intel will maintain information for these processors on our web site. You can access these processor family Web sites by clicking on the links under the processor column.