In the early days of the PC, motherboards (and pretty much every other device) was designed and built with discrete logic gates. If you were around in the days of the PC/XT and PC/AT, you probably remember the huge motherboards packed with over 150-200 individual ICs. Discrete ICs demanded a lot of power, and took up lots of room. It didn’t take designers long to realize that "standard" functions of the PC (like floppy drive interface circuits, DMA controllers, or programmable interrupt controllers) could be integrated onto Application-Specific ICs (or ASICs). With the use of ASICs, PCs were able to drop their chip count, reduce construction costs, and reduce power requirements.

But there are also performance advantages to such high levels of integration. Combining logic circuitry onto a single IC dramatically shortens the signal paths, and allows the circuit to operate at higher speeds. By optimizing the signal paths within the IC itself, performance could be improved even further. Designers quickly saw that they could integrate ALL the core logic needed to facilitate a complete PC in just a few highly-integrated ICs. Since these chips were specifically designed to be used as a set on the motherboard, they were dubbed the "chipset" (Fig. 11-1).

Today, chipsets play a leading role in the design and fabrication of modern personal computers. Where early motherboards could use hundreds of ICs, you’d be hard-pressed to find more than 20 ICs on a current motherboard. In fact, chipsets are SO important, that new chipsets must be developed to support each new feature or CPU. For example, you’ll find that Intel’s 430 TX chipset supports features such as SDRAM, dual CPUs, ACPI, and Ultra DMA - but the venerable 430 HX chipset does not. As a result, motherboards with a 430 HX chipset would have to be replaced with a motherboard using the 430 TX chipset before those features would be available. Ultimately, the overall features and capabilities of your PC are largely defined by the motherboard chipset (sometimes called core logic). This chapter is intended to familiarize you with many of the current chipsets in use today. If you want detailed technical information about today’s chipsets, you can usually download the complete manual from the chipset manufacturer’s web site (in Adobe Acrobat’s .PDF format). Table 11-1 lists the URLs for many chipset manuals.

Companion CD: The companion CD offers several utilities for the detection of core logic chipsets. For older motherboards, try SHOWS174.ZIP. For more recent systems, use CONF810E.ZIP which also provides a complete assessment of system information (highly recommended).

NOTE: There is a tremendous rivalry between the major chipset manufacturers. This chapter does NOT advocate the use of any given chipset (or manufacturer) over another, or attempt to make product recommendations. This chapter merely familiarizes you with the features of each chipset, and allows you to make objective assessments of system capabilities based upon the particular core logic in use.

While AMD (Advanced Micro Devices) is certainly no stranger to the CPU arena, they are relative newcomers to the chipset market. Traditionally, AMD relied on other chipset makers to support their line of CPUs (i.e. the 5x85, K5, and K6). However, not all chipset makers provided the optimum support for AMD’s products. As a consequence, AMD has developed the 640 chipset for use with their K6 CPU.

The AMD-640 chipset features two devices: the AMD-640 System Controller, and the AMD-645 Peripheral Bus Controller (Table 11-2). Working together, these chips can deliver numerous high-performance features that accelerate multimedia applications (especially those designed for MMX-type processors). The AMD-640 System Controller has been optimized to accelerate AMD-K6 processor transactions, and also incorporates support for SDRAM (Synchronous DRAM) - the most recent development in the evolution of main system memory. The AMD-645 Peripheral Bus Controller features support for Ultra DMA/33 which allows the ATA/IDE interface to provide a 33MB/s data transfer rate. System performance is further increased with Type F DMA, which provides a 5x improvement over standard DMA transfers. Type F DMA reduces the system bus requirements for DMA transfers, providing the CPU with greater access to the ISA bus (less of a bottleneck during data transfers). Perhaps most important for AMD, the 640 chipset is backward-compatible with existing AMD and Intel CPUs.

The AMD-640 System Controller features the 64-bit Socket 7 interface, integrated write-back cache controller, system memory controller, and PCI bus controller. The Socket 7 interface has been optimized for the AMD-K6 processor - providing 3-1-1-1-1-1-1-1 transfer timing for both read and write transactions from PBSRAM (Pipeline Burst Static RAM) at 66 MHz. The memory controller features a data buffering design that uses four cache lines (16 quad words or QW) of processor-to-DRAM or cache-to-DRAM write buffering with concurrent write-back capability to accelerate write-back and write-miss cycles. The integrated PCI bus controller features concurrent processor and PCI operation through a five-double word (or DW) posted write buffer design. PCI concurrency with DRAM or cache memory is achieved through a 48-double word post write buffer and 26-double word prefetch buffer.

The AMD-640 design also uses byte-merging which optimizes processor-to-PCI throughput and reduces PCI bus traffic by converting consecutive processor addresses into burst PCI cycles. The controller minimizes PCI initiator read latency and DRAM access using techniqies like snoop ahead, snoop filtering, forwarding cache write-backs to the PCI initiator, and merging L1 write-backs into the PCI-posted write buffers. The integrated PCI controller supports enhanced PCI bus commands such as Memory-Read-Line, Memory-Read-Multiple, and Memory-Write-Invalidate. These features allow a PCI initiator to achieve the full 133-Mbps burst transfer rate. The integrated PCI bus controller is fully compatible with the PCI Local Bus Specification (revision 2.1). You can see the AMD-640 employed in the system diagram of Fig. 11-2. Table 11-3 offers the AMD-640 chipset features at a glance.

The AMD-645 Peripheral Bus Controller features an integrated ISA bus controller, enhanced master mode PCI EIDE controller with Ultra DMA/33 technology, ACPI-compatible Power Management Unit, USB controller, PS2-compatible keyboard/mouse controller, and Real-Time Clock (RTC) with extended 256-byte CMOS RAM. The on-chip EIDE controller has a dual-channel DMA engine with capability of interlaced dual-channel commands. High-bandwidth PCI transfers are achieved by an enhanced 16 double-word data FIFO with full scatter and gather capability. The integrated USB controller features a root hub with two ports having 18-level-deep data FIFOs and built-in physical layer transceivers. The USB controller also offers backward compatibility with legacy keyboard and PS/2 mouse support. The AMD-645 Peripheral Bus Controller meets Microsoft Windows 95 Plug-and-Play requirements with steerable PCI interrupts, ISA interrupts, and DMA channels. The integrated power management unit is compliant with ACPI and APM, and provides dedicated input pins for external modem ring indication and power-on, five general-purpose I/O pins with option for I²C port, and 16 general-purpose pins that can be programmed as inputs or outputs.

Intel corporation provided the 8086 CPU that went into the first PC, and has led the way in CPU development ever since. Though competitors like AMD and Cyrix are narrowing the performance gap, Intel has managed to retain the lead in fast, high-performance CPUs like the Pentium II. Since Intel is the first to release new CPUs, they are also ideally positioned to develop the chipsets to complement those CPUs. Intel is also a frequent collaborator with Microsoft in the proposal of new industry initiatives (such as ACPI and AGP), so they often have a head-start in supporting those initiatives. Intel offers a wide range of chipsets.

The Intel 430 VX chipset (also referred to as the "Triton II" chipset) is found in relatively recent Pentium-based PCs designed for low-end or end-user applications (i.e. multimedia, games, and personal productivity software). The 430 VX chipset integrates support for the Universal Serial Bus (USB) standard, so home users can add a wide variety of Plug-and-Play digital input devices such as mice, keyboards, joysticks, scanners, and cameras. The 430 VX supports concurrent PCI architecture which maximizes system performance with simultaneous activity on the CPU, PCI and ISA buses. This generally improves video and audio performance for multimedia applications, and allows more high-speed peripherals in the systems without impacting the performance of the PCI bus. Improved EDO memory support, faster timing, and support for Synchronous DRAM (SDRAM) are also included. Memory support also allows the Shared Memory Buffer Architecture (SMBA) option. The Intel 430VX PCIset consists of the 82437VX System Controller, two 82438VX Data Paths, and the 82371SB PCI ISA IDE Xcelerator (PIIX3).

While the 430 VX is generally considered to be a good performer, there are some features which are noticeably absent. There is no support for multiple CPUs, and no support for ECC. The chipset will only handle up to 128MB of RAM (but only 64MB are cacheable). RAM timing is also a bit slower than the 430 HX, so 430TX systems tend to be a bit slower - even when SDRAM is installed. Table 11-4 outlines the features of the 430 VX chipset.

The 430 TX chipset optimizes the capabilities of the Intel Pentium processor with MMX technology (Pentium MMX), and has found "dual-duty" in both desktop and mobile PCs. Reduced power consumption enables new applications by delivering mobile-style power management to the desktop. The 430 TX chipset features Dynamic Power Management Architecture (DPMA) - extending the battery life of mobile computers, and enabling new power-efficient desktop models. Support for the Advanced Configuration and Power Interface (ACPI) also improves power management.

The 430 TX also supports the Ultra DMA disk drive protocol with the enhancements required for faster performance of today's multimedia applications. For higher memory throughput, the chip set supports Synchronous DRAM (or a mix of SDRAM and EDO RAM). Concurrent PCI support is available for the first time in a mobile PCI chip set, enabling faster and smoother video and audio performance. There is also support for the Universal Serial Bus (USB). With the "outside the box" Plug-and-Play capabilities of USB, the 430 TX chipset helps the integration of multimedia, I/O peripherals, and digital imaging devices.

The 430 TX also implements a full System Management Bus (SMBus) host controller with three-wire interface - through which the system can communicate with simple monitoring controllers. For example, "Smart Battery" devices can provide information to the power management charging system via the SMBus. The user can then be informed of the current battery state, along with an accurate prediction of the available operating time (or remaining time to fully charge the battery). Table 11-4 compares the features of the 430 TX.

The 430 TX chipset is a two-chip solution consisting of the 82439TX System Controller, and the 82371AB PCI ISA IDE Xcelerator. The 430TX forms a Host-to-PCI bridge, provides the second level (L2) cache control, and offers a full 64-bit data path to main memory. The System Controller integrates the cache and main memory DRAM control functions, and provides bus control for transfers between the CPU, cache, main memory, and the PCI bus. The L2 cache controller supports write-back cache for cache sizes of 256KB and 512KB (cache-less designs are also supported). Figure 11-3 illustrates an example block diagram of a 430 TX system.

The venerable 430 HX chipset (unofficially dubbed "Triton II") is perhaps the most well-known and well-respected Pentium chipset ever produced. With uncompromised EDO RAM timing, the 430 HX matches the performance of an asynchronous L2 cache-based system (without the cache). It supports 64Mbit DRAM, and offers 8 RAS lines (for up to 512MB of system memory). Memory address buffers are built into the system controller. Integrated deep-posting and FIFO buffers enable concurrent activity on both sides of the system controller and data paths for improved CPU utilization. ECC and parity memory support are integrated into the chip set, along with dual CPU support. The 430 HX supports concurrent PCI architecture, and the Universal Serial Bus (USB). The 430 HX chipset consists of the 82439HX System Controller and the 82371SB PCI I/O IDE Xcelerator (PIIX3). Table 11-4 lists the features of the 430 HX.

The 430 FX chipset (or "Triton" as it is unofficially known) was the first Intel Pentium chipset to become extremely successful - SO successful, in fact, that it is largely deemed to be the undoing of other competitors like ETEQ, UMC, and ALI. It was also the first x86-type chipset using EDO RAM (and is responsible for EDO now being a standard RAM type). Although the 430 FX is now obsolete, it is still considered to be a decent performer. Table 11-4 lists the specifications for the 430 FX chipset.

The 430 FX chipset consists of the 82437FX System Controller, two 82438FX Data Paths, and the 82371FB PCI ISA IDE Xcelerator (or PIIX). The chipset forms a Host-to-PCI bridge, provides second level (L2) cache control, and supports a full 64-bit data path to main memory. The System Controller integrates the cache and main memory DRAM control functions, and provides bus control for transfers between the CPU, cache, main memory, and the PCI bus. The L2 cache controller supports a write-back cache for cache sizes of 256KB and 512KB (cache-less designs are also supported). Cache memory can be implemented with either standard, burst, or pipelined burst SRAMs. An external Tag RAM is used for the address tag, and an internal Tag RAM handles the cache line status bits. The System Controller supports up to 128MB of main memory. An optimized PCI interface allows the CPU to sustain a high bandwidth to the graphics frame buffer at all frequencies. Using the snoop ahead feature, the System Controller allows PCI masters to achieve full PCI bandwidth. The Data Paths provide the connections between the CPU/cache, main memory, and PCI bus.

The 430 MX chipset is the first of Intel's complete mobile chipset solutions for the Pentium processor. The 430 MX employs many architectural innovations developed for the 430 FX chipset designed for desktop computers, and was designed for such uses as ProShare, high-speed Ethernet, and audio/graphic-intensive applications. The 430 MX chipset is ideally suited for any application that requires a faster bus (from 25 to 33MHz) for greater performance.

The 430 MX supports EDO RAM and pipelined burst SRAM. Its architecture provides greater than 100 MB/s PCI data streaming. The highly integrated Mode 4 local bus IDE controller improves the operation of fast hard drives. In addition, its integrated Plug-and-Play port makes systems easier to use and increases performance by transforming ISA motherboard peripherals into pseudo-PCI devices. As a mobile chipset, the 430 MX benefits from Advanced Power Management (APM) support.

The 430 MX chipset consists of the 82437MX System Controller, two 82438MX Data Paths, and the 82371MX PCI I/O IDE Xcelerator (or MPIIX). The 430 MX forms a Host-to-PCI bridge, provides the second level (L2) cache control, and supports a full 64-bit data path to main memory. The 82371MX MPIIX provides the bridge between the PCI bus and the ISA-like Extended I/O expansion bus. In addition, the 82371MX has an IDE interface that supports two IDE devices - providing an interface for IDE hard disks and CD-ROM drives. The MPIIX integrates many common I/O functions found in ISA-based PC systems - a seven-channel DMA controller, two 82C59 interrupt controllers, a 8254 timer/counter, Intel SMM power management support, and control logic for NMI generation. Chip select decoding is provided for the BIOS, real time clock, and keyboard controller. Edge/Level interrupts and interrupt steering are supported for PCI Plug-and-Play compatibility.

The 440 FX chipset (unofficially referred to as the "Natoma" chipset) is a highly integrated solution for supporting Pentium II and Pentium Pro processors in mainstream business systems. This second-generation chipset optimizes system performance for 32-bit application software in 32-bit operating system environments, and will support multiple CPUs. Based on concurrent PCI architecture, the 440 FX chipset includes a multi-transaction timer (MTT) for enhanced video transfer and higher frame rates, and a passive release mechanism for improved MPEG and audio performance. There is also enhanced write performance for full utilization of write buffers (to improve host-based processing applications) and PCI delayed transactions to ensure CPU-to-ISA write control compatibility with the PCI 2.1 specification.

The 440 FX chipset is slated for compact designs implemented in a four-layer board (in either the ATX, baby AT, or LPX form factors). The chipset supports up to 1GB maximum memory size using flexible memory options including EDO RAM. Memory is further enhanced with ECC support. The 440 FX also utilizes the PIIX3 - allowing motherboards to use the same I/O subsystems as those used with the 430 HX and 430 VX. Universal Serial Bus (USB) support allows for Plug-and-Play connectivity "outside the box", and Bus Master IDE (BMIDE) handles access for fast hard drives. Table 11-5 lists the features for a 440 FX chipset. The 440 FX chipset consists of the 82441FX PCI and Memory Controller, the 82442FX Data Bus Accelerator, and the 82371SB PCI ISA IDE Xcelerator (or PIIX3).

The 450 GX chipset (known as the "Orion" chipset) is designed to support Pentium Pro processor servers and scientific systems - especially those which use multiple CPUs (up to four). By comparison, the 450 KX (also sometimes referred to as "Orion") is aimed at designers of workstations and high-performance desktops with one or two CPUs. In actual practice, the 450 GX/KX chipsets are rarely used because of the many features the chipsets lack. Neither supports concurrent PCI, USB, or any form of I/O management. When compared with other contemporary chipsets, the 450 GX/KX are simply not as competitive as the more recent 440 FX chipset. Table 11-5 highlights the features of the 450 GX/KX chipset.

The 440 LX chipset is the first in a series of AGP (Accelerated Graphics Port) chipsets from Intel designed to optimize the performance of a Pentium II processor. This is seen as a major new computing platform for small business, large business, and home users alike. The 440 LX chipset with AGP extends the system bandwidth to the graphics controller, and optimizes the system bandwidth and concurrency with the implementation of Quad Port Acceleration (QPA). QPA provides 4-port concurrent arbitration of the processor bus, graphics bus, PCI bus, and SDRAM.

The 440 LX chipset also offers advanced power management and fast resume from powered-down states through Advanced Configuration and Power Interface (ACPI). This enables local power down operation, with remote wake up for off-hours maintenance. Application performance for 3D graphics are improved. AGP gives PCs the capability to handle memory-intensive 3D graphics applications, providing the faster performance and enabling larger textures out of main memory - resulting in more life-like image detail.

The 82443LX PCI AGP System Controller integrates a Host-to-PCI bridge, optimized DRAM controller and data path, and an Accelerated Graphics Port (AGP) interface into a single chip. The I/O subsystem portion of the 440 LX is the 82371AB which provides an ISA bridge, a PCI ISA IDE Xcelerator (PIIX4), and USB controller. Table 11-6 lists the features for the 440LX chipset.

Founded in 1987, VIA is perhaps the greatest threat to Intel’s dominance of the chipset market. Their line of Apollo chipsets has provided an effective alternative for the support of Intel Pentium/MMX/Pro, AMD K5 and K6, and Cyrix 6x86 and M2 CPUs. VIA chipsets are generally recognized as full-featured, high-performance solutions which are used on many motherboards. VIA also produces a selection of network and peripheral controller ICs for computer applications.

VIA’s VT82C680 Apollo P6 is a high-performance energy-efficient chipset for PCI/ISA desktop and notebook PC systems based on 64-bit Intel Pentium Pro processors. The chipset supports multiple Pentium Pro configurations (based on Intel GTL+), and handles up to 66MHz external CPU bus speed. The chipset also supports the Pentium Pro CPU multi-phase protocols for split transactions and eight level deep in-order queue for optimal CPU throughput. The DRAM and PCI bus are also independently powered so that each of the buses can be run at 3.3v or 5v (the ISA bus always runs at 5v). Figure 11-4 illustrates a system block diagram of the Apollo P6 chipset. The main features of the Apollo P6 chipset are listed in Table 11-7.

The Apollo VP3 is a high-performance, two-chip chipset for the implementation of AGP, PCI, and ISA bus architectures in desktop and notebook PC systems based on 64-bit Socket-7 CPUs (including Intel Pentium and Pentium MMX, AMD K5 and K6, and Cyrix/IBM 6x86 and 6x86MX processors). The Apollo VP3 chipset consists of the VT82C597 system controller and the VT82C586B PCI to ISA bridge. The VT82C597 system controller provides superior performance between the CPU, optional synchronous cache, DRAM, AGP bus, and the PCI bus with pipelined, burst, and concurrent operation. The VT82C597 complies with the Accelerated Graphics Port Specification 1.0 and features a 66MHz master system bus. It is interesting to note that the VP3 chipset is one of the few that provide AGP support for non-Pentium Pro processors. Figure 11-5 illustrates the typical block diagram for a VP3 chipset, and the key features for the chipset are shown in Table 11-8.

The two-chip VIA Apollo VP2/97 is the industry’s most highly integrated, high-performance Socket 7 compliant chipset. With ECC, Microsoft PC-97 compliance, SDRAM, 512MB DRAM, and 2MB cache support, the VP2/97 offers remarkable versatility for Intel Pentium, Pentium MMX, Cyrix/IBM 6x86 and 6x86MX, and AMD K5 and K6 MMX processors.

The Apollo VP2/97 builds on the VIA VT82C580VP Apollo VP (widely recognized as a leading Socket 7 chipset. Additonal performance related features include a fast DRAM controller with support for SDRAM, EDO, BEDO, and FPM DRAM types in mixed combinations with 32/64 bit data bus widths and row and column addressing, a deeper buffer with enhanced performance, an intelligent PCI bus controller with concurrent PCI master/CPU/IDE operations, and zero-wait-state PCI master and slave burst transfer rates. The Apollo VP2/97 features the VIA VT82C586B PCI-IDE controller chip which supports ACPI/OnNow, Ultra-DMA/33, and USB technologies. Figure 11-6 illustrates the VP2 chipset in use. Table 11-9 lists the main features of the chipset.

The VIA VT82C580VPX Apollo VPX/97 core logic chipset is a high-performance four-chip solution for Socket 7 main boards supporting Intel Pentium, Pentium MMX, Cyrix/IBM 6x86 and 6x86MX, and AMD K5 and K6 MMX processors. To enable proper implementation of the Cyrix/IBM 6x86 200+ processor, the chipset features an asynchronous CPU bus which operates at either 66 or 75MHz speeds. Apollo VPX/97 also supports the Cyrix/IBM linear burst mode.

The Apollo VPX/97 features a fast DRAM controller with support for SDRAM, EDO, BEDO and FPM DRAM types in mixed combinations of 32 or 64-bit data bus widths. Additional features include a deeper buffer with enhanced performance, an intelligent PCI bus controller with concurrent PCI master/CPU/IDE operations, and zero-wait-state PCI master and slave burst transfer rates. There is support for up to 2MB of L2 cache, and up to 512MB of DRAM. The VIA Apollo VPX/97 features the VIA VT82C586B PCI-IDE controller chip which complies with the Microsoft PC-97industry standard by supporting ACPI/OnNow, Ultra-DMA/33, and USB technologies. You can see the general layout of a VPX/97 chipset in Fig. 11-7. Table 11-10 lists the key features of the Apollo VPX/97.

The VT82C580VP Apollo VP-1 is a four-chip solution for PCI/ISA desktop and notebook PCs based on Pentium, AMD K5x86, and Cyrix 6x86 CPUs. Apollo VP-1 features functions designed to bypass conventional board-level bottlenecks (including burst and normal EDO RAM, FPM RAM, and SDRAM support, burst SRAM and cache module support, and an on-board dual channel enhanced master mode PCI IDE controller that supports up to four Enhanced IDE (EIDE) devices. The VIA Apollo VP-1 chipset consists of one VT82C585VP System Controller, a VT82C586 PCI/IDE/ISA/USB Controller, and two VT82C587VP Share Frame Buffers. Figure 11-8 shows a diagram of the VP-1 chipset. The features of the VP-1 are listed in Table 11-11.

The VT82C570M Apollo Master is an older chipset for PCI/ISA desktop PCs based on Intel Pentium, AMD K5x86, and Cyrix 6x86 CPUs. The VIA Apollo Master consists of a VT82C575M System Controller, a VT82C576M PCI/ISA/IDE controller, two VT82C577M Frame Buffers, and a VT82C416 Support IC. There are few features which would now be considered advanced, but Table 11-12 lists the main features.

SiS is another major manufacturer of chipsets which support core logic (motherboards) as well as mobile PCs and multimedia applications. Although SiS is a bit behind VIA and Intel in chipset development, they are rather unique in the inclusion of video accelerator hardware into the chipset (particularly in their later products). This makes SiS chipsets particularly appealing to entry-level PCs where minimizing cost is very important. Since SiS products are not as widely used as other chipsets, you’ll find summaries of SiS chipset features in the following tables:

• SiS5597 chipset; Table 11-12
• SiS5596 chipset; Table 11-13
• SiS5571 chipset; Table 11-14
• SiS551X chipset; Table 11-15
• SiS85C49X chipset; Table 11-16

Founded in 1989, OPTi is a well-known supplier of core logic and multimedia chipsets to manufacturers of desktop and mobile computer products world-wide. Although the chipsets by Intel and VIA have pushed OPTi into the background, they continue to produce some respected motherboard chipsets.

The OPTi Discovery chipset (82C650/651) provides a highly integrated solution for a wide range of fully compatible, high-performance PC platforms based on the Intel Pentium Pro processor (Fig. 11-9). The Discovery chipset is comprised of two chips, the 82C650 System Controller, and the 82C651 Bus Controller (and an optional third chip - the 82C652 - which provides an auxiliary PCI bus that can be used as the AGP port). It provides 64-bit core logic, integrated PCI (revision 2.1), support for a second Host-to-PCI device (the 82C652), support for all popular memory technologies, sophisticated power management features, as well as optional support for Unified Memory Architecture (UMA) and the Accelerated Graphics Port (AGP). The deep buffers and several levels of pipelining minimize system level latencies and maximize/sustain throughputs for all the major subsystems. Support for parity/ECC protection provides enhanced levels of fault tolerance to greatly improve the reliability of the system.

The OPTi Vendetta (82C750) single-chip core logic unit provides a highly integrated solution for high-performance PC platforms (Fig.11-10). It supports the Intel 3.3V Pentium, Cyrix 6x86, and AMD 5K86. In addition to supporting a wide range or platform designs, the 82C750 feature set also includes audio and one game port functionality, Common Architecture support, isolated primary/secondary Ultra-DMA IDE support, and dual USB ports. This makes the Vendetta an ideal choice for multimedia-based end-user systems.

OPTi's FireStar single-chip core logic combines high-performance features with space saving design ideal for mobile applications (Fig. 11-11). This solution is based on the Intel 3.3V and 2.5V (split voltage) Pentium MMX, Cyrix M2, and AMD K6 processors. FireStar also allows FPM DRAM, EDO DRAM, or Synchronous DRAM (SDRAM) as options when designing the system. The highly concurrent cycles and deep buffering features of FireStar also improve the system’s performance. For power management applications, FireStar offers power saving modes for extended battery life and provides true CPU temperature monitoring. In STPGNT mode, CPU power consumption can be reduced by 80%. In STPCLK mode, CPU power consumption can be reduced by as much as 99%. FireStar also features advanced fail-safe thermal management, full peripheral activity tracking and power-off control, Advanced Configuration and Power Interface (ACPI) support, and Advanced Power Management (APM), as well as "suspend to memory" and "suspend to disk" power management options.

Although this chapter is intended to highlight many of the most popular motherboard chipsets in use today, there are a great many more older chips and chipsets still in the field. The myriad of 386 and 486-class systems still in service almost guarantee that you’ll encounter these "legacy" chips sooner or later. It is almost impossible to adequately list ALL the chips and chipsets that have been employed in PCs throughout the years, but Table 11-17 attempts to cover the more popular devices (as well as other support ICs which may still be in use).

This finishes up Chapter 11. Be sure to review the glossary and chapter questions on the accompanying CD. If you have access to the Internet, take some time to review a few of the chipset makers listed below:

AMD: http://www.amd.com

Intel: http://developer.intel.com/design/pcisets/

VIA: http://www.via.com.tw/

SIS: http://www.sisworld.com/

Opti: http://www.opti.com

VLSI: http://www.vlsi.com