Hardware Secrets
Home | Audio | Case | Cooling | CPU | Input | Memory | Mobile | Motherboard | Networking | Power | Storage | Video | Other
Content
Articles
First Look
News
Reviews
Tutorials
Main Menu
About Us
Awarded Products
Compare Prices
Datasheets
Dictionary
Download
Drivers
Forums
Gabriel's Blog
Links
Manufacturer Finder
Newsletter
On The Web
RSS Feed
Test Your Skills
Newsletter
Subscribe today!
Search




Recommended Book
The Winn L. Rosch Hardware Bible (6th Edition)
By Winn L Rosch
Que
Price: $0.25

Home » Motherboard
Everything You Need to Know About Chipsets
Author: Gabriel Torres
Type: Tutorials Last Updated: September 7, 2005
Page: 4 of 4
$ Check REAL-TIME pricing for ASUS P5N-E SLI (90-MBB5G0-G0EAY00Z) Motherboard $
eBay: $98.95 Bestbuy: $279.99
Jr: $369.99 Netrithms: $379.99

Inter-Bridge Architecture

When the bridge concept started to be used, the communication between the north bridge and the south bridge was done thru this bus, as we show on Figure 5. The problem of this approach is that the bandwidth available for the PCI bus – 132 MB/s – will be shared between all PCI devices in the system and devices hooked to the south bridge – especially hard disk drives. At that time, this wasn’t a problem, since hard drives maximum transfer rates were of 8 MB/s and 16 MB/s.

Inter-Bridge Architecture
click to enlarge
Figure 5: Communication between north and south bridges using the PCI bus.

But when high-end video cards (at that time, the video cards were PCI) and high-performance hard disk drives were launched, a bottleneck situation arouse. Just think of modern ATA/133 hard disk drives, which have the same theoretical maximum transfer rate as the PCI bus! So, in theory, an ATA/133 hard drive would “kill” and the entire bandwidth, slowing down the communication speed of all devices connected to the PCI bus.

For the high-end video cards, the solution was the creation of a new bus connected directly to the north bridge, called AGP (Accelerated Graphics Port).

The final solution came when the chipset manufacturers started using a new approach: using a dedicated high-speed bus between north and south bridges and connecting the PCI bus devices to the south bridge.

Inter-Bridge Architecture
click to enlarge
Figure 6: Communication between north and south bridges using a dedicated bus.

When Intel started using this architecture it started calling the bridges as “hubs”, the north bridge became MCH (Memory Controller Hub) and the south bridge became ICH (I/O Controller Hub). It is just a matter of nomenclature in order to clarify the architecture that is being used.

Using this new architecture, which is the architecture that motherboards use nowadays, when the CPU reads data from a hard drive, the data is transferred from the hard drive to the south bridge, then to the north bridge (using the dedicated bus) and then to the CPU (or directly to memory, if the Bus Mastering – a.k.a. DMA – method is being used). As you can see, the PCI bus is not used at all on this transfer, what didn’t happen on the previous architecture, since the PCI bus was in the middle of the road.

The speed of this dedicated bus depends on the chipset model. For example, on Intel 925X chipset this bus has a maximum transfer speed of 2 GB/s. Also, the manufacturers call this bus with different names:

  • Intel: DMI (Direct Media Interface) or Intel Hub Architecture (*)
  • ULi/ALi: HyperTransport
  • VIA: V-Link
  • SiS: MuTIOL (**)
  • ATI: A-Link or PCI Express
  • nVidia: HyperTransport (**)

(*) DMI interface is newer, used on i915 and i925 chipsets on and uses two separated data paths, one for data transmission and another for reception (full-duplex communication). Intel Hub Architecture, used by previous chipsets, uses the same data path for both transmission and reception (half-duplex communication).

(**) Some nVidia and SiS chipsets use only one chip, i.e. i.e. the functionalities of both north and south bridges are integrated into a single chip.

Also, on Radeon Xpress 200 from ATI, the communication between north and south bridges uses two PCI Express lanes. This doesn’t affect the performance of the system, because contrary to PCI, PCI Express bus is not shared between all PCI Express devices. It is a point-to-point solution, which means that the bus only connect two devices, the receiver and the transmitter; no other device can be attached to this connection. One lane is used for data transmission and the other for data reception (full-duplex communication).

HyperTransport bus also uses separated data paths, one for data transmission and another for reception (full-duplex communication). Click here to learn more about this bus.

If you want to know the details of a given chipset, just go to the chipset manufacturer website. Here you can find a complete list of chipset manufacturers and their websites.

As a last comment, you may be wondering what is “on-board PCI devices” listed on Figures 5 and 6. On-board devices like LAN and audio can be controlled by the chipset (south bridge) or by an extra controller chip. When this second approach is used, this controller chip is connected to the PCI bus.

Pages (4): « 1 2 3 [4]
Print Version | Send to Friend | | Bookmark Article | Comments (0)

Related Content
  • ATI Radeon Xpress 200 for Intel Platform
  • nVidia GeForce 6100 and nForce 400 Chipset Family
  • What is High Definition Audio
  • Thermaltake Extreme Spirit II
  • Intel Chipset Codenames Cross-Reference Table

  • Recommended Deals
    ASUS Rampage II Extreme Intel X58 Core i7 Extreme/Core i7 Socket 1366 PC3-14400 (DDR3-1800) ATX Moth... Motherboard


    PCNation: $405.20 TigerDirect.com: $419.99
    CompUSA.com: $419.99 Jr: $328.99
    FOXCONN A79A-S AMD 790FX AM2+/AM2 Phenom FX/Phenom/Athlon /Sempron Socket AM2/AM2+ 2600 MHz PC2-8500... (6943296901894) Motherboard


    CompuVest: $177.18 Dell: $259.99
    Dell SMB: $259.99 Dell Small Business: $259.99
    Amazon.com Marketplace: $223.40 Ink Oasis: $165.95
    FOXCONN G33M-S Core 2 Quad Socket 775 1333MHz PC2-6400 (DDR2-800) mATX Motherboard Retail


    Dell SMB: $95.99 Compuvest: $97.05
    Amazon.com Marketplace: $109.40 Ink Oasis: $95.65
    Dell Small Business: $95.99 CompuDirect: $84.00
    MSI G31M3-L V2 Core 2 Quad/Core 2 Duo/Pentium® D/Pentium 4/Celeron Socket 775 1333 MHz PC2-6400 (DD... Motherboard


    Amazon: $51.14 CompUSA.com: $49.99
    Simple-upgrade: $65.90
    MSI P45 Neo3-FR Intel P45 Core 2 Extreme/Core 2 Duo/Core 2 Quad Socket 775 1600 MHz PC2-8500 (DDR2-1... Motherboard


    CompuVest: $121.56 CompUSA.com: $124.99
    J&R Music and Computer World: $122.99 TigerDirect.com: $124.99
    PCNation: $127.23 Jr: $174.99

    RSSLatest News
    New Desktop Processors From Intel
    December 1, 2008 - 2:59 PM PST
    New Fans From Thermalright
    November 28, 2008 - 4:44 AM PST
    Glacialtech Launches UFO V51 CPU Cooler
    November 27, 2008 - 3:18 PM PST
    Lexar Media Launches Triple-Channel DDR3 kits for Core i7 Processors
    November 26, 2008 - 6:23 PM PST
    OCZ Intros Fatal1ty Power Supplies
    November 26, 2008 - 5:53 PM PST
    Hynix Introduces 7 Gbps GDDR5 Memory Chips
    November 25, 2008 - 6:42 PM PST
    Geil Launches EVO Cyclone Memory Cooler
    November 24, 2008 - 6:19 PM PST
    Cooler Master Intros New Silent Force Power Supplies
    November 24, 2008 - 5:56 PM PST
    Akasa Launches Smart Fan Case Fans
    November 21, 2008 - 2:58 PM PST
    Titan Launches Cooler for Intel Core i7 CPUs
    November 20, 2008 - 4:47 PM PST
    .:: More News ::.

    RSSLatest Content
    Nintendo DS Lite Ice Blue Pack Review
    New Page: Awarded Products
    KeyScan KS810 Keyboard-Scanner Review
    Everything You Need to Know About Camera Sensors
    Zalman ZM750-HP Power Supply Review
    How does or would your notebook improve your quality of life? What role does or would it play in your life?
    SilverStone Decathlon 700 W Power Supply Review
    Antec Signature 650 Power Supply Review
    Seventeam ST-550P-AG Power Supply Review
    Logitech QuickCam Pro 9000 Review
    GeForce GTX 260 with 216 cores Video Card Review
    Laptop Design: What are some ways that form can enhance function?
    Panasonic Link-to-Cell Phone System Review
    Topower TOP-1100P10 Power Supply Review
    Gigabyte MA78GM-S2H Motherboard

    Our Most Popular Articles
    Maximum CPU Temperature
    829,200 views
    nVidia Chips Comparison Table
    517,106 views
    AMD ATI Chips Comparison Table
    454,947 views
    How to Find Out Your Motherboard Manufacturer and Model
    440,424 views
    ATI Radeon X1300 Pro Review
    431,212 views
    ATI Radeon X1600 XT Review
    424,633 views
    Connecting Two PCs Using a USB-USB Cable
    390,917 views
    How To Correctly Apply Thermal Grease
    373,870 views
    Sempron vs. Athlon XP
    291,593 views
    Sempron 3400+ Review
    283,727 views

    Latest Threads in Our Forums
    New Desktop Processors From Intel
    by Hardware Secrets Team
    Nintendo DS Lite Ice Blue Pack Review
    by Hardware Secrets Team
    Build or buy - long post..
    by Aknot
    Can viruses really steal ID information?
    by cs0khunter82
    Cases: How to Avoid Overheating
    by Merman
    need help building gaming desktop under $1.5k
    by ray-solomon
    Need help what to buy for PC build
    by ray-solomon
    UpGrade BIOS
    by Philphoto
    Too much thermal grease? [pics]
    by darkabis315
    How long have you been with Vista?
    by cs0khunter82
    .:: Visit Our Forums ::.


    © 2004-8, Hardware Secrets, LLC. All rights reserved.
    Advertising | Legal Information | Privacy Policy
    All times are Pacific Standard Time (PST, GMT -08:00)