Motherboard Chipsets Roundup

A chipset is a group of integrated circuits and microprocessors connected together to accomplish a specific task. An integral part of a motherboard is the chipset; all the features that the motherboard supports are built around it.

Last few months have seen grassroot changes in motherboard chipsets and processors; adding both variety as well as confusion in the market. This article takes a closer look at the latest chipsets and their value proposition.

There are five major players in the motherboard chipsets segments, namely Intel, VIA, SIS, nVidia and ATI. While ATI and Intel make chipsets exclusively for Intel processors, nVidia has its solution only for AMD-based machines. VIA and SiS, on the other hand have solutions for both platforms.

Chipsets for the AMD 939 pin processor: nVidia nForce 3 Ultra



The nVidia nForce 3 chipset comes in three types, ultra, pro and go for the AMD 64, Opteron and mobile platforms, respectively. Here we discuss the nForce3 ultra, which is a solution for the desktop. 

While comparing motherboards in the last issue (25 Motherboards Tested, page 126) we found that all motherboards support Ethernet connection on board. The nForce 3 chipset is one of the first chipsets in this category that offers Gigabit LAN to the user. Though presently this feature is being used in very few environments because of low penetration of Gigabit, it is definitely a good technology for the future.

The chipset also offers hardware support for RAID 0 and 1, and supports up to four SATA drives.

SiS 756 (Northbridge)/965 (Southbridge)



This chipset boasts of being the first of its kind that supports the PCI Express with the Athlon 64 FX. The chipset supports one PCI Express X16 slot for graphics and two PCI Express X1 ports.

Combined with the latest 965 Southbridge, it can offer up to four SATA ports with an optional RAID 1 hardware support. The MuTIOL interconnect between the Northbridge and Southbridge is also proprietory to SiS. It can offer up to 1 Gbps of bandwidth. 

The chipset also backs the ACR (Advanced Communications Riser) card. This is the specification that replaces the AMR (Audio/ Modem Riser) port, though is backward compatible with it. The 120 pin ACR slot can take the 46 pin AMR cards. 



The ACR can be used to extend USB, LAN, HomePNA, modem and audio. 

HomePNA (Home Phoneline Networking Alliance) is a LAN technology which is used to create a small network using the existing phone wires for Internet connection sharing. 

VIA K8T890



This is also one of the latest in the bandwagon of PCI Express enabled chipsets for the AMD 64 platform. But, the difference in this chipset lies in the way it can be implemented. 

One major highlight of this chipset is the Flex Express Architecture, which offers motherboard manufacturers greater

flexibility in providing PCI Express functionality in their motherboards. The chipset provides 20 PCI Express lanes, which can be used in a variety of

combinations. For instance, these can be used to incorporate two PCI Express slots for graphics card to give a dual-display option on the motherboard. Or, these can be used to incorporate

up to five PCI Express slots for other devices.

Or you can have a single 16X PCI Express graphics port and four PCI Express X1 ports. Moreover, these four PCI Express X1 ports connect directly to the Northbridge, which is different from conventional chipsets, wherein the connection is only through the Southbridge. 

Other important features in conjunction with the VIA VT8237 Southbridge include the on board 6-channel audio, SATA RAID and onboard modem. The 6-channel audio and 100 Mbps Ethernet are extendable to 8-channel and Gigabit LAN respectively by using PCI companion controllers.

Chipsets for Intel P4: Intel 915



Part of the latest chipsets that support the LGA 775 processors from Intel, the 915 comes with a lot of new features as compared with the earlier 865/875 chipsets. Starting from support for PCI Express for graphics and DDR2 memory running in dual channel it offers all new audio and video capabilities. The graphics are enhanced using the Intel Graphics Media Accelerator 900 that adds support for Microsoft DirectX 9 on the chipset itself. The sound is enhanced through Intel High Definition Audio, which is Dolby and DTS compatible and supports 8-channel surround sound.

SiS649 and SiS 656



These two chipsets are essentially similar in nature except for the memory that they support. The SiS649 supports DDR2 533/DDR-400 in single channel while the 656 supports DDR2-667/ DDR-400 in dual channel. The latter is believed to significantly improve system performance.

The differentiation has been done taking into account the market segments. While the 656 chipset will cater to the enthusiast, the 649 will cater to the value segment. Other significant features of the chipset include 800 MHz FSB, PCI Express X16 graphics and two additional PCI Express X1 ports. These Northbridge chipsets are connected with the same SiS Southbridge chipset that's used for the AMD processors. It offers SATA controller and RAID functionalities.

Geetaj Channana