Home > Articles

Server Chipsets

This chapter is from the book

This chapter is from the book

Broadcom ServerWorks Chipsets for Intel Processors

Starting in 1997, ServerWorks (a Broadcom company originally known as Reliance Computer Corporation) introduced its first server chipsets for Intel processors. Today, ServerWorks is second only to Intel as the major supplier of server chipsets for Intel-based servers.

Early ServerWorks chipsets included the ServerSet I (also known as the Champion 1.0 chipset) and the ServerSet II. ServerSet I supported up to six Pentium Pro processors and featured two 32-bit PCI buses. ServerSet II supported up to four Pentium II Xeon processors and featured a 64-bit PCI bus. These chipsets were discontinued several years ago.

Current ServerWorks chipsets support the Pentium III Xeon and Xeon DP and MP (based on Pentium 4) processors. Although ServerWorks uses the North Bridge and South Bridge terminology for its chipsets, its current chipsets also include memory controller and I/O bridge chips. Thus, ServerWorks chipsets more closely resemble E7xxx-series Intel chipsets than Intel's 8xx or 9xx chipsets.

Several major motherboard and system builders, including Intel, have used Champion- and Grand Champion–series chipsets for multiprocessor server motherboards and systems.

ServerWorks Chipsets for Intel Pentium III Xeon Processors

ServerWorks currently makes three chipsets for the Pentium III Xeon processors:

  • Champion HE (also known as Champion Enterprise)— Supports up to four processors with 100MHz FSB; the North Bridge is the NB6536 2.0HE.
  • Champion HE-SL (also known as Champion Volume)— Supports up to two processors with 133/100MHz FSB; the North Bridge is the NB6576.
  • Champion LE (also known as Champion Entry)— Supports up to two processors with 133/100MHz FSB; the North Bridge is the NB6635 3.0LE.

Originally, this series of chipsets was known as the ServerSet III series.

All three North Bridge chips can be paired with either the OSB4 or CSB5 South Bridge chip to form a chipset. The OSB4 features UDMA/33 ATA/IDE hard disk host adapter, USB 1.1 ports, and an LPC connection to a Super I/O chip. The CSB5 features an UDMA/100 ATA/IDE hard disk host adapter, USB 1.1 ports, and an LPC connection to a Super I/O chip. Most motherboards that use a Champion-series chipset use SCSI-based hard disks or RAID arrays instead of ATA hard disks, so there is little practical difference between these South Bridge chips.

Table 3.14 provides an overview of the Champion series of chipsets for the Pentium III Xeon processor.

Table 3.14. Champion Chipsets for Pentium III Xeon

View Table

The Champion LE Chipset

The Champion LE chipset is the simplest of the current Champion series, using only North Bridge and South Bridge chips. For greater reliability than with desktop-adapted chipsets, Champion LE, like all current ServerWorks server chipsets, uses registered memory.

Champion LE supports two 64-bit/66MHz PCI expansion slots via the South Bridge chip. However, if you need additional 64-bit slots, Champion LE is not a suitable choice. Thus, Champion LE is best suited to basic dual-processor server applications.

The Champion HE-SL Chipset

Although the Champion HE-SL chipset supports two processors, as does the Champion LE, it is a more powerful and flexible chipset. It supports AGP 2x graphics, and ECC registered memory must be installed in matched pairs to support memory interleaving for better memory performance.

However, the most significant improvement in Champion HE-SL over its Champion LE sibling is its support for both 3.3V (66MHz) and 5V (33MHz) 64-bit PCI slots. This comes via the third component in the HE-SL chipset, the CIOB20 I/O bridge. The CIOB20 (also known as the NB6555 IO Bridge 2.0 chip), provides a 64-bit PCI bridge between the North Bridge and 64-bit PCI slots. The connection to the North Bridge uses ServerWorks's own Inter Module Bus (IMB) high-speed connection. IMB runs at 1GBps, which is four times faster than Intel's Hub Architecture 1.0 or 1.5 or the VIA V-Link 4x interconnections.

If you need to use several PCI cards (33MHz or 66MHz) in a server, the Champion HE-SL is a better choice than the Champion LE.

The Champion HE Chipset

The Champion HE is the most powerful of the Champion series. It supports four Pentium III Xeon processors and uses a fourth ServerWorks chipset component, the MADP memory controller chip. In a four-way configuration, four MADP chips are used, but in a two-way configuration, only one MADP chip is used (see Figure 3.24).


Figure 3.24 The ServerWorks Champion HE chipset in a typical four-way configuration.

The MADP chip supports memory interleaving for better memory performance in both two-way and four-way configurations.

ServerWorks Chipsets for Intel Xeon Processors

ServerWorks currently makes three chipsets for the Xeon processors based on the Pentium 4:

  • Grand Champion HE (also known as Grand Champion Enterprise)— Supports up to four processors with 400MHz FSB; the North Bridge chip is called CMIC-HE.
  • Grand Champion LE (also known as Grand Champion Volume)— Supports up to two processors with 533/400MHz FSB; the North Bridge chip is called CMIC-SL.
  • Grand Champion SL (also known as Grand Champion Entry)— Supports up to two processors with 533/400MHz FSB; the North Bridge chip is called CMIC-LE.

Originally, this series of chipsets was to be known as the ServerSet IV series.

All three North Bridge chips can be paired with either the CSB5 or CSB6 South Bridge chip to form a chipset. The CSB6 is the most advanced South Bridge chip used by any ServerWorks chipset to date. It includes three ATA-100 ATA/IDE host adapters; support for ATA RAID 0, 1, and 5; 64-bit PCI bus; 400MBps connection to the North Bridge; and USB 1.1 ports.

Table 3.15 provides an overview of the Grand Champion series of chipsets for Xeon processors.

Table 3.15. Grand Champion Chipsets for Intel Xeon

View Table

The GC-SL (Grand Champion Entry) Chipset

The Grand Champion SL chipset is the simplest of the current Grand Champion series. Its North Bridge chip incorporates a single IMB I/O interface and a single Thin-IMB interface to the South Bridge. It supports up to 4GB of RAM. RAM contents are protected with 128-bit ECC and spare memory technologies. The optional CIOB-E bridge provides Gigabit Ethernet support, while the optional CIOB-X2 I/O bridge provides PCI-X support up to 133MHz. In its basic North Bridge/South Bridge configuration, Grand Champion SL is suitable for basic server designs. However, when the CIOB-X2 PCI-X bridge is added, it is also suitable for midrange server designs.

The GC-LE (Grand Champion LE) Chipset

The dual-processor Grand Champion LE is designed to handle four times the memory (16GB) of the Grand Champion SL. It also supports two CIOB-X2 PCI-X I/O bridge chips, enabling a motherboard to have up to six PCI-X 100/66MHz cards, up to three PCI-X 133MHz cards or a mix of PCI-X cards and onboard devices. Thus, if you need support for several PCI-X cards, or a mix of PCI-X cards, a high-speed integrated SCSI host adapter and a Gigabit Ethernet adapter as in Figure 3.25, the Grand Champion GC-LE chipset is a better choice than the GC-SL.


Figure 3.25 A typical implementation of the Grand Champion LE server chipset.

Figure 3.25 illustrates the block diagram of a typical server using the GC-LE chipset.

The GC-HE (Grand Champion HE) Chipset

The Grand Champion HE is the most powerful of the Grand Champion series. It supports four Xeon MP processors and incorporates three IMB I/O interfaces for the fastest memory interfacing of any GC-series ServerWorks chipset. With support for up to 64GB of memory, its memory contents are protected with 128-bit ECC, chipkill, spare memory, memory mirroring, and hot-plug memory card support technologies. The GC-HE uses five REMC memory controller chips in a four-way configuration: four in the data path and a fifth one in the address path.

Figure 3.26 illustrates a four-way implementation of the GC-HE chipset.


Figure 3.26 A typical implementation of the Grand Champion HE server chipset.

ServerWorks South Bridge and Support Chips

All ServerWorks Champion and Grand Champion chipsets contain South Bridge chips, and many of them also contain I/O bridge and memory controller chips. The South Bridge chips used by ServerWorks chipsets support ATA/IDE, PCI, and legacy I/O devices. Table 3.16 provides more information about the South Bridge chips used with Champion and Grand Champion chipsets.

Table 3.16. Champion/Grand Champion South Bridge Chips

View Table

The I/O bridge chips provide support for PCI-X slots and, in some versions, Gigabit Ethernet. Table 3.17 provides more information about the I/O bridges used by the Champion and Grand Champion chipsets.

Table 3.17. Champion/Grand Champion I/O Bridge Chips

View Table

The high-end HE and GC-HE chipsets also use memory controller chips to provide support for memory interleaving. Memory interleaving divides memory into banks, permitting memory to be accessed more quickly for improved performance. Table 3.18 provides more information about these chips.

Table 3.18. Champion/Grand Champion Memory Controller Chips

View Table

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020