Pentium Socket 7 Chipset Information

Last Update: Thursday, July 30, 1998 11:09


Chipset General Informations

The Chipset is a set of chips located on the motherboard that perform all of the most essential functions of a computer system.

Below is a table summarising some of  the functions and properties controlled by the Chipset:

  • The bus speed (33, 40, 50, 55, 60, 66, 75, 83, 100 MHz)
  • The PCI/ISA Brigde
  • The Support for the onboard HDD EIDE or SCSI controller and  their feature (DMA mode, PIO mode).
  • The DMA controller
  • The IRQ Controller
  • The Memory types supported (FPM, EDO, BEDO, SDRAM, parity-checking, ECC)
  • The Maximum Size of the Memory Modules (16, 32, 64, 128 Mb)
  • The Maximum Memory Area Cachable (64, 512, 1024 Mb)
  • The Secondary Level 2 (L2) cache type (burst, pipeline burst, synchronous, asynchronous)
  • The CPU type (486, P-24T, P5, P54C/P55C, Pentium Pro, Pentium II)
  • The nature pf the PCI bus (synchronous or asynchronous)
  • The number of CPU supported (single, dual, quad)
  • The Plug & Play features
  • The special features supported (AGP, IrDA, USB, PS/2)


As we can see the chispset is one the most important component on the motherboard if not the most important. The Chipset can be compared to a dispatch center where the CPU would be the command center. Every single bit of information stored in the memory or sent to any I/O device has to pass through the chipset on its way to the CPU. All peripherals uses the chipset to access other peripherals and to establish their data transactions with the CPU.

The chipset is the real maestro and this is so true that when new chipsets emerge, motherboard manufacturers redesign their boards to accommodate them. All the hardware installed on acomputer system has to be choosen to fit the Chipset specifications. For instance using an Ultra DMA enhanced hard disk drive on a 430HX chipset will not allow any performances gain over a DMA mode 2 enhanced hard disk drive for the simple reason that the 430HX chipset does'nt support the Ultra DMA mode!

The following table summarise some of the most important function accomplished by the chipsets:

Chipset Features Informations

HDD CONTROLLER

Onboard Disk Drives controllers may now be found on most of the modern motherboards and many of its supported features are actually controlled by the Chipset.

Here is a listing of some of these features:

  • Hard Disk Drive Type
  • PIO Modes and DMA modes
  • Number of Hard Disk Drives
  • Bus Mastering
  • Data Transfer Rates

The installed chipset is very important so care must be taken to make sure that it is supporting every features you need.

THE DMA CONTROLLER

This controller main function is to allow peripherals to establish data transaction without the intervention of the CPU to lessen the CPU usage.

Here is a listing os some of the devices using the DMA controller:

  • Floppy Disk Drives
  • Hard Disk Drives
  • CD-ROM Drives
  • PCI SCSI controllers
  • Soundboards
  • Grapic Cards

The more devices using the DMA controller the less CPU usage is required therefore freeing the CPU to concentrate on other important tasks.

THE PROCESSORS SPEEDS

The variety of processors speeds supported by the chipset is a good indication of the expendability of the motherboard using it.

For instance some Pentium class motherboard are limited to 166mhz CPU while some others can be upgraded up to 200mhz CPUs. Typical Pentium chipset will support bus speeds of 50 to 66 MHz with a multiplier range of 1.5x to 3x. This enable support for 75,to 200 MHz CPU.

In some cases a processor may not be supported just because the motherboard does'nt have the right socket. For instance a socket 7 motheroboad cant allow the use of a Pentium II CPU.

PCI/ISA BRIDGES

The PCI/ISA bridge is a function of the chipset required to rely the information from the ISA bus to the PCI bus or vice versa and to or from other  peripherals of the computer system.

THE MMX SUPPORT

The chipset is not controlling any of the MMX features so only the motherboard voltage planes will decide if MMX enhanced CPU are supported or not on a given motherboard !

IRQ CONTROLLER

The interrupt controller is the device used to rely the numerous interrupt request issued from all peripherals asking to be serviced by the CPU. IRQ are requested to service peripherals devices.

THE AGP SUPPORT

The AGP is a new feature found on Intel's 440LX chipset based motherboards. This slots is specifically designed to take advantage of the latest AGP enhanced 3D graphic cards. For more information about the AGP you can click here and read the bottom section of my motherboard information page where i give a more detailed explanation of the AGP slot.

THE PLUG & PLAY

Plug & Play is a feature allowing devices to set them self their own usage of the system resources. However for some reason it is often required to manually set these resources to avoid conflicts.

For instance installing a new modem might stealth one of your sound card IRQ! So, care must be taken when using this feature!

THE BUS CONTROL

PC compatible uses two buses. The ISA bus which for the slower 8-bits and 16-bits peripherals and the PCI bus for 32-bits  the high-speed devices.The chipset controls these buses, and manages all data transactions to and from them. The chipset's decides what type of buses it will support, what speed they will be able to run as well as all additional features they may be supporting.


The following table is comparing some of the most popular Pentium Chipsets features and could be
used as a guide to help you choose a motherboard that will support all the features you are looking for.

Pentium Socket 7 Chipset Features comparison
FEATURE VIA Chipset Intel Chipset Sis Chipset

Processor Support
Chipset no: VPX/97 VP2/97 VP3 MVP3 430HX 430VX 430TX 5571 5591
PentiumŪ Y Y Y Y Y Y Y Y Y
Cyrix 6x86TM MX Y Y Y Y Y Y Y Y Y
AMD K6TM Y Y Y Y Y Y Y Y Y
IDT WinChipTM Y Y Y Y * * * ?? ??

Bus Features Support
Chipset no: VPX/97 VP2/97 VP3 MVP3 430HX 430VX 430TX 5571 5591
PCI 2.1 Y Y Y Y Y Y Y Y Y
EISA Support N N N ? Y N N N ?
AGP Support N N Y Y N N N N Y

L1 Cache
Chipset no: VPX/97 VP2/97 VP3 MVP3 430HX 430VX 430TX 5571 5591
Write Policy WB/WT WB/WT WB/WT WB/WT WB WB WB WB WB
Linear Burst Y Y Y Y N N N Y ??

L2 Cache
Chipset no: VPX/97 VP2/97 VP3 MVP3 430HX 430VX 430TX 5571 5591
Max. Cache size 2MB 2MB 2MB 2MB 512KB 512KB 512KB 512KB 1MB
Max. Bus speed Mhz 75 66 66 100 66 66 66 83 100
Cache type Async
PB		 Sync
PB		 Sync
PB		 Pseudo
Sync/PB		 Sync
PB		 Sync
PB		 Sync
PB		 Syncc
PB		 Sync
PB
Cachable area 512MB 512MB 1GB 1GB 512MB 64MB 64MB ?? ??
Cache Timing 3-1-1-1 3-1-1-1 3-1-1-1 3-1-1-1 3-1-1-1 3-1-1-1 3-1-1-1 3-1-1-1 3-1-1-1

DRAM Interface
Chipset no: VPX/97 VP2/97 VP3 MVP3 430HX 430VX 430TX 5571 5591
Max. DRAM 512MB 512MB 1024MB 1024MB 512MB 128MB 256MB 512MB 768MB

EDO Timing

 4-2-2-2 4-2-2-2 4-2-2-2 4-2-2-2 5-2-2-2 5-2-2-2 5-2-2-2 5-2-2-2 5-2-2-2

SDRAM Timing

 3-1-1-1 3-1-1-1 3-1-1-1 3-1-1-1 ? 7-1-1-1 5-1-1-1 6-1-1-1 5-1-1-1

Supported Memory Types
Chipset no: VPX/97 VP2/97 VP3 MVP3 430HX 430VX 430TX 5571 5591
FPM Y Y Y Y Y Y Y Y Y
ECC N Y Y Y Y N N N Y
EDO Y Y Y Y Y Y Y Y Y
BEDO Y Y N N N N N N N
SDRAM Y Y Y Y N Y Y Y Y
DDR
SDRAM		 N N Y Y N N N N N

Integrated Feautres
Chipset no: VPX/97 VP2/97 VP3 MVP3 430HX 430VX 430TX 5571 5591
Ultra DMA-33 Y Y Y Y N N Y N Y
EIDE Interface Y Y Y Y Y Y Y ?? ??
USB Y Y Y Y Y Y Y Y Y
Integrated KBC Y Y Y Y ? ? N Y Y
Integrated RTC Y Y Y Y ? ? Y Y Y
Number of chip 4 2 2 2 2 4 2 1 2

Miscellaneous
Chipset no: VPX/97 VP2/97 VP3 MVP3 430HX 430VX 430TX 5571 5591
ACPI Unit N Y Y Y N N Y ?? Y

    * Officially Intel Chipset do not support non Intel Cpu higher than 66Mhz !!!