Everything you wanted to know about Motherboards


Oct 11, 2000 (Updated Jan 3, 2002)


The Bottom Line Lots of geek grammar to understand to pick the right motherboard.

A computers motherboard is one of the most important parts of the computer. Without it, nothing else can run since it's what everything else has to plug into.

This guide is part of a much longer topic, but I have decided to place this section here.

The very first thing you have to look at on a motherboard is what your target CPU is. If you are taking the Intel road, choose a socket-370 motherboard for Celeron and Pentium III's. If you are going to get a Pentium IV, then you will need a motherboard that fits the Pentium IV(Socket 423) AND a case that supports it as well. If you are taking the AMD Athlon/Duron route, choose a Socket-A motherboard.

There are various motherboard styles to fit different case designs. ATX motherboards can be up to the maximum 12" by 12" size and will have the maximum number of PCI slots available. MiniATX, MicroATX, and FlexATX form factors are designed for smaller cases that have less expansion room. These form factors usually have 3 or 4 expansion slots instead of the maximum 7 on a full size ATX board. The Mattel Barbie and Hotwheels PC's are FlexATX chassis and contain very small motherboards; they also have very few expansion slots (can you even add anything to these things?) Avoid the small boards if you have a large case, because you will only be limiting your expansion ability, they do not offer any sufficient cost savings. There are some motherboards still being made in the BabyAT form factor, which is designed for an AT case, avoid these as well if you are not looking to use an AT case. AT boards have the older style of Keyboard connector and have no USB or PS/2 ports "on-board" they require a header to place them in one of the expansion slots.

The chipset matters as well, Intel CPU's work best with Intel chipsets. So look for an i815EP (if you want integrated video get the i815E, or get the i810E) based motherboard. There are also alternatives like the ALi, SiS, and ATI-S370 chipsets (I have yet to see the ATI-S370 chipset appear in any motherboard.) nVidia is also working on a core logic chipset as well. The alternative chipset motherboards cost less money, but they are very problematic if you do not know what you are doing. Many problems resulting from the use of these motherboards are either due to poor-design/manufacturing or from end-users that do not follow directions.

The Pentium IV uses the i850 Chipset and it always uses the ICH2(Like the i810E2/i815E/i815EP)

Motherboards have many types of slots on them. At the most there will be 1 AGP slot for the video card. A maximum of 7 PCI cards is possible, however this would mean there is no AGP slot, so 6 is the usual maximum. Some motherboards might still have an ISA slot on them, however it is not recommended to use it since it will disable some ACPI power management functions. Older motherboards might have more than one ISA slot on them, which limits your PCI expansion slot availability. Usually 1 ISA slot that is on some motherboards is shared with the last PCI slot, giving you the option of never using it. AMR and CMR headers/slots you should not even give a thought about, you can not purchase any retail parts to go in these slots, and any OEM AMR/CMR parts that a pre-assembled system has is designed for removal only in order to replace it with an identical part or to use the PCI slot beside it.

The chipset matters as well with AMD chipsets. AMD produces their own chipsets, but AMD also lists on their website what processor works with what motherboard by the 3rd parties.
See http://www1.amd.com/athlon/config for recommended Athlon Motherboards, and http://www1.amd.com/duron/mbl for recommended Duron Motherboards.

See http://www.teleport.com/~ffsupprt/ini_supp/motherboard.htm for a listing of motherboard vendors.

See http://kisai.epinions.com/cmhd-Motherboards-All for Epinions listing of Motherboard opinions.

Features common to most motherboards:

AGP Slot - This is for your video card. It is on i815 motherboards as well as most AMD and 3rd party chipset motherboards. Look for 4X or 8X(coming soon) AGP.

PCI Slots - Peripheral Connect Interface, this is for your expansion cards. Most motherboards have 2-6 of them. It is better to have 6 when possible since this maximizes your expansion ability.

SDRAM slots - This is for your RAM (memory.) There should be at least 2 of them and usually have a maximum of 4. Intel i815 chipset motherboards will usually only have 2 of them, motherboards for AMD processors and 3rd party boards will usually have 4 of them. SDRAM comes in PC66, PC100, PC133, and soon PC266 speed. Any memory you purchase must match the support in the PC. i810/815 series chipsets can not take more than 512MB of memory. i810 series can only take PC100. If you need more than 512MB and are using a Celeron or Pentium III, you will have to use a VIA or ALI chipset.

Pentium IV's (using the i850)use RAMBUS memory and can take up to 4 RDRAM channels.

USB ports - Universal Serial Bus ports. Most motherboards since 1997 have these as standard equipment. There are usually 2 USB ports on the I/O panel side of the motherboard, but there maybe more on a cable for placing at the front of the case. The ICH2 has 2 USB Controllers, so they can have 4 USB ports (i810E2/i815E/i815EP/i850.)

UltraATA 33/66/100 - Many hard drives are now supporting the UltraATA 100 specification. Having matching cables and hard drives will increase system performance.
i810E/i815/i815P chipsets support ATA33/66, i810E2/i815EP/i815E chipsets support ATA100.

ACPI BIOS - This allows for the Operating system to completely take control of configuration and power management. ACPI replaces Plug-and-Play BIOS, which the BIOS controlled the hardware resources, and the power management through APM. ACPI BIOSĀEare backwards compatible with Plug-and-Play Operating systems like Windows 95 and 98.

Optional features:

CMR/AMR header - These are for software-based OEM parts. Usually for a software modem, DSL modem, or AC97 codec. These parts you will not find in retail boxes. AMR slots usually take away one of your PCI slots, whereas CMR headers usually do not. Most AMR/CMR parts are software based. You canít mix and match AMR/CMR hardware from different vendors.
CMR headers are shared with the neighboring PCI slots, so you cannot use the CMR header with an expansion card in the slot beside it.

Serial and Parallel ports - Now considered legacy devices, these ports are considered slow and out of date. You only need this port for hobby-electronics and old legacy hardware. USB to parallel port and USB to serial port adaptors are available for Windows 98 but do not work any other Operating system.

USB 2.0 ports - Might be soon available, these are high-speed versions of USB 1, however are also partly incompatible. If you use a USB 2.0 port and a USB 2.0 Device but only a USB 1.0 USB hub, the hub will not work. Using USB 2.0 requires replacing any USB 1.0 hubs and extension cables.

Connectors for Chassis security, LED's and a speaker - Many motherboards have these, but it's up to you if you want to hook them up. These are usually "header" pins; the actual parts you hook up might not exist in your computers chassis.

Temperature/Voltage monitoring - Overheating detection and detection of bad configurations.

Firewire - Some motherboards may have onboard Firewire or IEEE 1394 support, if you plan on hooking up a DV/MiniDV or D8 video camera to your computer, this is the best way to do it, it also saves you from having to purchase an analog capture card or separate IEEE1934 card. However the onboard chips are usually software codec style and utilize the system CPU for processing.

Onboard Audio - Many motherboards are coming with onboard audio, however most implementations are software-based, and use the CPU for digital processing. If you want to pay a little more now, you can skip purchasing a separate audio card later and still be able to upgrade the audio system. Onboard audio on i810/i815 chipsets is optional, it's usually on i810E2 and i815E/EP chipsets that use the ICH2, but on i810/i815/i815P that use the ICH it may be optional (ICH) or present (ICH0.)

Onboard Video - Some motherboards have onboard Video, the onboard video performance usually suffers since it relies on the CPU and system memory bandwidth for performance. Intel variations (i810/i810e and i815) have baseline 3D performance. The i815/i815E variation allows for addition of an AGP video card. The i815P/EP do NOT have onboard Video. The i810 series have no AGP port, so you cannot add an AGP video card at a later time. The ATI-S370 (The same technology is used in the Nintendo GAMECUBE) version of onboard video is apparently better in performance than the onboard video of the i810/i810e and i815, but has yet to appear in any motherboard implementation. Onboard video will save you a great deal of money, however the performance hit in 3D software leaves onboard video only usable in some markets, mainly business applications and internet terminals. If you want to save yourself some money initially, get the i815 chipset based onboard video for Intel CPUís, you can then put an AGP video card in later to replace it when you can afford it. ALi currently offers an onboard TNT2 graphics subsystem in their integrated video motherboard chipset.

Onboard LAN - You can save yourself some money by having onboard LAN on the motherboard (motherboards that have it usually have 10/100 fast Ethernet chips.) However as with most other onboard components, it will usually use more CPU time than a separate Ethernet card. Intel Chipsets that use the ICH2 (i810E2/i815E/815EP/i850) have this.

Onboard SCSI - Onboard SCSI usually increases the price of the motherboard considerably. Unless you are going to use the onboard SCSI, skip it. Separate SCSI cards will have Externally accessible SCSI ports as well as internal connectors for SCSI drives. Onboard SCSI usually only has onboard connectors for hard drives. If the onboard SCSI host adaptor dies, the entire motherboard has to be replaced if there are no PCI slots to put in a replacement SCSI host adaptor.

Onboard-anything - The general problem with onboard components is that if one part dies and you have no free expansion slots, you have to then replace the entire motherboard. Replacing the entire motherboard is more expensive than replacing the individual components. The upgrade cost is also more since if you want to replace the motherboard; you have to get another motherboard with all the same onboard components. Unlike having all the parts separate, which allows you to use any motherboard regardless of the onboard equipment, and still retain all your working parts. Onboard LAN and Onboard Audio usually lower the total cost of building the computer by 60-300$, whereas Onboard Video and Onboard SCSI will save 60-1200$, but the initial investment in the motherboard is considerably higher.

Dual Processor - You need to be running Windows NT, Linux or any other OS that supports Dual processors in order to make use of both processors. You cannot use Windows 95,98,98SE,ME or DOS and use the second processor. Most games designed for Windows are designed with Windows 9X in mind, so they will not benefit very much from multiple processors.

Jumper-free - Voltage, Bus speeds, and other settings are controlled through software, which lowers the maintenance of the computer. In a jumper-free software controlled motherboard, you adjust voltage and bus speeds in software, and if you make an error in setting something, the computer only has to be rebooted for it to correct itself. This feature has been available on most motherboards since 1999. Jumper-free mode also allows for over-clocking the CPU, changing Bus Speeds, and changing memory timings.

The most important factors in considering the motherboard is to look at Memory bandwidth (If it can use PC133 or PC2100 DDR memory, PC2100 is faster), Drive interface (UltraATA 33/66/100), and AGP support (2X AGP, 4X AGP, 8X AGP, AGP Pro.) The most important factor is if it is the correct socket/slot type for your processor. Intel Pentium III and Celeronís use a Socket-370 (older Pentium IIIís, Celerons and Pentium IIís use Slot 1) connector. AMD Athlon and Duron use a Socket-A connector (Older Athlons use a Slot A connector which is the same size as the Slot 1 connector but incompatible with it.) The Pentium 4 uses socket 423 which is totally incompatible with Pentium III chips. The second important factor is the core logic chipset used. Using a chipset that is the same as the company that makes the CPU guarantees the best compatibility, however 3rd party chipsets offer more or different features, some features are broken on motherboards that features 3rd party chipsets. (A certain 3rd party chipset does not work in 4X AGP mode when an nVidia Geforce video card is used.)

Choose a motherboard that meets your needs. There is very little performance difference between all the brands that use the same chipset.
Asus (www.asus.com) makes probably the best quality motherboards; they also add some of their own goodies to their boards. Abit is also a popular brand, which is due to it having features that suit over-clocking CPU's.

Before printing, please note that this editorial is a little over 5 pages long. Questions and comments can be sent to kisai_z@yahoo.com


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