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  1. Describe the EMI Filter
  2. What is a VRM and why is it important?
  3. What does "Novell Ready" mean?
  4. What is ICAS?
  5. What is Pipeline Burst SRAM?
  6. What is the difference between PIO mode 3 and PIO mode 4?
  7. What is PnP?
  8. What is Bus Master IDE?
  9. What is the PCI expansion bus?
  10. Why do motherboards include ISA slots?
  11. What is a Flash ROM BIOS?
  12. What is meant by the term "Green PC"?
  13. What is a UART 16C550 serial port?
  14. Explain the PICO fuse
  15. What is Universal Serial Bus (USB)?
  16. Why should every PC and peripheral have an USB?
  17. What is the "blank cache" controversy?
  18. What is MMX?
  19. What is NLX motherboard?
  20. What is an ATX and it's benefits?
  21. What is Pentium II Processor?
  22. What is S.E.C. cartridge packaging?
  23. What is DIB?
  24. What is AGP?

Describe the EMI Filter?

The EMI (Electro Magnetic Interference) filter is used near all I/O connectors of the circuit board and serves the function of preventing Electro magnetic interference. It is necessary to design such a filter to pass the FCC regulations. The FCC issues regulations to assure the EMI from electronic devices does not interfere with the operation of radio/TV/communications devices; in the US, all computing devices are required to comply with these regulations. The filter is usually made of iron powder.

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What is a VRM and why is it important?

The voltage regulator module, or VRM, enables the motherboard to support future Pentium processors (P55C+ series). These new processors will run at faster speeds (150 MHz and above) than today’s models and will require different operating voltages.

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What does "Novell® Ready" mean?

Novell® certification of their systems is very important for system integrators and resellers. The term "Novell® Ready" means that the components delivered in the bare bone system can be integrated into a finished system that will pass the certification tests of Novell® and therefore can be used in any system where Novell® compatibility is crucial.

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What is ASIC?

ASIC or Application Specific Integrated Circuits are the most popular type of integrated circuit used for the core logic and other non-CPU supporting chipsets on motherboards and expansion boards. Motherboards using ASICs are faster and more reliable than their predecessors, because ASICs allow a greater integration of functions on one chip, thereby reducing the number of chips on the motherboard.

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What is Pipeline Burst SRAM?

Pipeline Burst SRAM (PB SRAM) is a type of SRAM that can support Pentium-based system boards. PB SRAM on average outperforms systems using standard SRAM on average of 7.5% and by up to 15%-16% when using applications in Windows®.

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What is the difference between PIO mode 3 and PIO mode 4?

PIO mode 3 and PIO mode 4, by reducing the IDE cycle time and reducing the IDE HDD memory cycle, increase the IDE data transfer rate and, therefore, enhance system performance. With this new approach, the traditional transfer rate, which is 3.33 Mbps (Mode 0), can be increased to 11.11 Mbps (PIO Mode 3) and 16.67 Mbps (PIO Mode 4).

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What is PnP?

PnP or Plug and Play refers to the ability of a computer system to automatically adapt to the addition of expansion boards and other add-on devices. A system that is plug and play compatible lets the user plug in a device and use it, without worrying setting DIP switches, jumpers, and other configuration elements: the system BIOS automatically adjusts to the presence of plug and play compatible add-on devices. Microsoft® and Intel® developed the specifications for plug and play in 1993. Since then many manufacturers have adopted this new standard.

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What is Bus Master IDE?

Bus Master IDE is a chipset designed to overcome the limitations of IDE-to-memory data transfers. It enables the CPU to operate more efficiently when handling simultaneous events.

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What is the PCI expansion bus?

PCI (Peripheral Component Interconnect) was developed by Intel and other big PC companies and was designed to make full use of the power of the Pentium processor.

The PCI Local Bus was developed to enable PC innovation in:


-allow second to none graphics for PCs

-overcome standard bus limitations


-E.g., multimedia, motion video at volume price points


-Highly integrated systems

-Lowest cost peripherals

-Investment spans multiple CPU generations by driving a component-to-component connection standard for PCs, to complement existing board-to-board connection standards.

Performances Features Include:

  • Data bursting as normal operating mode-both read & write
  • Linear burst ordering
  • Concurrency support (deadlock, buffering solutions)
  • Low latency guarantees for real time devices
  • Access oriented arbitration (not time slice).

Cost Features Include:

  • No connection glue; no external data buffers
  • Low pin count interface
  • Implementation in existing ASIC technologies

Reliability Features Include:

  • Thorough electrical design for multiple loads at 33MHz
  • Error detection, reporting

Flexibility Features Include:

  • Processor independent; peripherals off processor "treadmill"
  • Multimedia support
  • Compatible with existing expansion standards
  • Scalability designed in from the beginning
  • Applicable from laptop to server

Protocol Features Include:

  • Multi-master; peer-to-peer
  • 32 bit multiplexed; processor independent
  • Low pin count; 45 slave; 47 master
  • Synchronous, 8-33MHz (132 Mbytes/sec)
  • Variable length, linear bursting-read & write
  • Parity on address, data, command
  • Concurrency/pipelining support
  • Initialization hooks for auto-configuration
  • Arbitration: central, access oriented, "hidden"
  • 64-bit extension transparently interoperable with 32-bit
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Why do motherboards include ISA slots?

AOpen motherboards and bare systems, like most modern PC systems, include both PCI expansion slots and ISA expansion slots. ISA (Industry Standard Architecture) is the older of the two bus standards.

It was introduced with the IBM®-AT system architecture and was the first improvement on the 8-bit bus design of the IBM-XT. ISA is a 16-bit data bus that operates at 8 or 10mhz with a throughput of 6Mps. It became a de facto standard, and until recently was the most widely used type of expansion slot. However, ISA could not handle the processing requirements of the new devices developed to exploit the power of newer CPU models that greatly exceeded the processing speed of the 80286 processor of the IBM-AT.

ISA expansion slots are included in our motherboards today to accommodate users who need to upgrade to faster processors but still require compatibility with older peripherals. ISA slots are also useful for add-on cards like sound and fax modem cards.

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What is a Flash ROM BIOS?

The motherboard houses your BIOS (Basic Input/Output System). Some motherboards use a removable chip to provide BIOS services. When you want to upgrade the BIOS, it may cost you up to $50.00 for the replacement part. Better motherboards use Flash BIOS, which allows you to use a software routine to upgrade the BIOS without ever opening the case. AOpen motherboards feature a Flash BIOS, and upgrades can be downloaded from AOpen’s bulletin board and Web site (

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What is meant by the term "Green PC?"

A "green" PC complies with the energy consumption guidelines issued by the U.S. Environmental Protection Agency. The guidelines were issued to minimize the energy consumption related to personal computers. Energy Star devices, or "green" devices, can detect when they are idle and switch to a low-energy mode in which they consume 30 watts or less. AOpen’s "Green" function is the feature of the motherboard that implements the energy saving modes required for Energy Star compliance.

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What is UART 16C550 serial port?

The UART 16550 chip is the most recent development in chipsets handling RS232 serial port communications. It was developed to handle the demands of modern high seed telecommunications. This chip can handle more sophisticated communications tasks than its predecessors such as the 8250 UART and 16450 UART, including the extra workload of operating under a multi-tasking environment like Microsoft® Windows®, OS/2® or UNIX®. Serial ports that rely on the older UART chips should only be used for simple tasks such as supporting a mouse. AOpen motherboards feature UART 16C550 serial ports.

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Explain the PICO fuse.

PICO fuse is used to protect the motherboard from a power surge coming from the keyboard connectors. There is a possibility of generating a power surge when plugging or unplugging the keyboard while the power is on. The fuse is required to attain UL safety certification.

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What is Universal Serial Bus (USB)?

Universal Serial Bus (USB) is a virtually unlimited "outside the box" expansion. Hassles over add-on cards, dip switches, jumpers, IRQs, DMA channels and I/O addresses should be a thing of the past. With USB, users can attach and detach peripherals without opening the computer, or even shutting it down. USB also provides an opportunity for exciting new digital peripherals including digital cameras and digital joysticks for multi-user games.

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Why should every PC and peripheral have an USB?

1. Easy Plug and Play Functionality. USB allows virtually unlimited PC expansion. With USB, PC users no longer need to worry about selecting the right serial port, installing expansion cards or the headache of configuring dip switches, jumper cables, software drivers, IRQ settings, DMA channels and I/O addresses.

USB employs a "one-size-fits-all" connector that allows PC users to install and remove peripherals without opening the computer. The "hot insertion and removal" feature enables users to install and detach peripherals while their PC stays up and running. And while USB makes it easy to add existing devices, it also paves the way for exciting new digital peripherals.

2. Universal Compatibility. USB provides a single industry wide Plug and Play standard that takes the guesswork out of expanding PC functionality. The USB standard is currently supported by more than 250 leading computer, telecommunications and software companies. Intel is a charter member of the USB Implementor Forum.

3. Simpler Peripheral Design. Eliminating the need for expansion cards makes peripherals easier to design and manufacture. In addition, the universal compatibility inherent in USB architecture eliminates much of the expense of testing and validation of different combinations of peripherals and software.

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What is the "blank cache" controversy?

The blank cache controversy arose from instances of fraud in the motherboard market. Unscrupulous motherboard makers replaced functioning cache chips (SRAM) with chips that had the appearance of a working SRAM chip but lacked the necessary internal circuitry – these chips have been referred to as blank because they look like the real thing but don’t provide any memory capacity. By inserting phony SRAM chips where working chips should have been, the motherboard makers were able to avoid the cost of using real chips – of course, they charged the regular price for the motherboards, thus illegally boosting their profits.

This fraud is possible because the system BIOS can be set as if an adequate amount of cache was present even when in fact phony blank cache has been substituted for real SRAM. The best way to avoid being victimized by a blank cache scam is to limit your motherboard purchases to manufacturers with worldwide reputations for quality and integrity.

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What is MMX?

The Pentium processor with MMX technology is the newest addition to the Pentium processor family and offers micro-architectural enhancements over previous members of the Pentium processor family.

The Intel MMX technology is based on SIMD technique—Single Instruction, Multiple Data—, which enables increased performance on a wide variety of multimedia and communications applications. The Pentium processor with MMX technology supports fifty-seven new instructions, as well as new packed data types. All existing operating systems and application software are fully compatible with the Pentium processor with MMX technology.

On chip level 1 data and code cache sizes have been doubled to 16KB each on the Pentium processor with MMX technology. Larger separate internal caches improve performance by reducing the average memory access time and providing fast access to recently used instructions and data. The instruction and data caches can be accessed simultaneously while the dual-ported data cache supports two data references simultaneously. The data cache supports a write-back policy for memory updates.

Dynamic branch prediction uses the Branch Target Buffer (BTB) to boost performance by predicting the most likely set of instructions to be executed. The BTB has been improved on the Pentium processor with MMX technology to increase its accuracy.

To improve performance, an additional pipeline stage has been added.

A pool of four write buffers is now shared between the dual pipelines to improve memory write performance.

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What is NLX motherboard?

NLX is a new low profile motherboard form factor designed to improve upon today’s low profile form factors and to adapt to new market trends and PC technologies. NLX does the following:

  • Supports current and future processor technologies
  • Supports new Accelerated Graphics Port (AGP) high performance graphics solutions.
  • Supports tall memory technology
  • Provides more system level design and integration flexibility

The add-in card riser is located at the right edge of the motherboard.

The processor is located at the front, left section of the motherboard, improving thermal and clearance issues.

Taller components such as the processor and tall memory are preferred to be located on the left side of the motherboard, allowing the I/O slots to hold full length add-in cards in many system configurations.

At the back of the motherboard, the I/O connectors are stacked single and double high to support more connectors.

Several PC vendors worldwide jointly to define the NLX form factor and to incorporate flexibility to accommodate the best designs for current and future PCs. NLX is a public specification intended for widespread use in many types of systems.

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What is an ATX and its’ benefits?

The ATX specification has been written as a specification for the PC industry designed to add value to the PC. It defines a new PC form-factor that will allow PC manufacturers to build products more cheaply, improve ease of use and serviceability, and incorporate new and exciting I/O feature with ease. The ATX form factor is essentially a Baby-AT baseboard rotated 90 degrees within the chassis enclosure and a new mounting configuration for the power supply. In this way, the processor is relocated away from the expansion slots, allowing them all to hold full-length add-in cards. ATX defines a double height aperture to the rear of the chassis, which can be used to host a wide range of on-board I/O. Only the size and position of this aperture is defined, allowing PC manufacturers to add new I/O features to systems that will help them differentiate their products in the marketplace, and better meet the needs of end-users.

A change to the system form-factor is ultimately of little benefit if it does not reduce overall system cost. ATX achieves this in a number of ways.

  • By integrating more I/O down onto the board and better positioning the hard drive and floppy connector’s material cost of cables and add-in cards is reduced.
  • By reducing the number of cables and components in the system, manufacturing time and inventory holding costs are reduced and reliability will increase.
  • By using an optimized power supply, it’s possible to reduce cooling costs and lower acoustical noise. An ATX power supply, which has a side-mounted fan, allows direct cooling of the processor and add-in cards making a secondary fan or active heat sink unnecessary in most system applications.

ATX is a specification that is freely available to the whole industry. The current version (2.0) incorporates feedback from the many chassis and power supply vendors making ATX products.

Release 2.01 of the ATX Specification makes minor adjustments to Release 2.0, which incorporated a number of new features, additional requirements, and clarifications. These changes take into account support for the next generation of ATX motherboards, while maintaining compatibility with the first generation. Readers should examine their combinations of motherboard, power supply and chassis needs to determine whether they require the additional features found in Release 2.01.

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What is Pentium II Processor?

The Pentium II processor is the most advanced processor with Intel MMX media enhancement technology. Delivering Intel’s highest performance, the Pentium II processor has plenty of performance headroom for the applications you need, such as business media, PC imaging, Internet communications and more.

Running at 300MHz for desktops, workstations and servers, the processor uses the high-performance Dual Independent Bus technology to deliver high bandwidth to fit with its high processing power. The Single Edge Contact (S.E.C.) cartridge design includes a dedicated 512KB level two cache. The Pentium II processor also includes 32KB of L1 cache, twice that of the Pentium Pro processor.

Error Correction Code (ECC) is now available on the L2 cache of the Pentium II processor for added data integrity and reliability, making the Pentium II processor the preferred choice for single and dual processor workgroup and web servers.

Product Features:

  • Dual Independent Bus Architecture: Like the Pentium Pro processor, the Pentium II processor also uses the D.I.B. architecture. The high-performance technology combines both a dedicated, high-speed L2 cache bus and advance system bus that enable multiple simultaneous transactions. Two buses plus a faster l2 cache equals no waiting.
  • Intel MMX technology: Intel’s media enhancement technology enables the Pentium II processor to deliver higher performance for media, communication and 3D applications.
  • Dynamic Execution: The Pentium II processor uses the unique combination of processing techniques, first used in the Pentium Pro processor, to speed up software performance.
  • Single Edge Contact cartridge: Intel’s new innovative packaging design for this and future processors, the S.E.E. cartridge, allows all of the Pentium II processor’s high performance technologies to be delivered in today’s mainstream systems.
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What is S.E.C. cartridge packaging?

The Single Edge Contact (S.E.C.) cartridge is Intel’s innovative packaging design that enables even higher performance to be delivered to mainstream systems.

Using this technology, the core and L2 cache are fully enclosed in a plastic and metal cartridge. These sub-components are surface mounted directly to a substrate inside the cartridge to enable high-frequency operation. The S.E.C. cartridge technology allows the use of widely available high-performance industry BSRAMs for the dedicated L2 cache, enabling high-performance processing at mainstream price points. Also, this cartridge technology allows the Pentium II processor to use the same high performance Dual Independent Bus architecture used in the Pentium Pro processor.

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What is DIB?

In order to meet the demands of applications and to provide headroom for future generations of processors, Intel has developed the Dual Independent Bus (DIB) architecture to address bandwidth limitations in the current PC platform architecture.

The Dual Independent Bus architecture was first implemented in the Pentium Pro processor and will become broadly available with the Pentium II processor. Intel created the dual independent bus architecture to aid processor bus bandwidth. Having two (dual) independent buses enables the Pentium II processor to access data from either of its buses simultaneously and in parallel, rather than a singular sequential manner as in a single bus system.

Together these Dual Independent Bus architecture improvements offer up to three times the bandwidth performance over a single bus architecture processor. In addition, the Dual Independent Bus architecture supports the evolution of today’s 66MHz system memory bus to higher speeds in the future. This high-bandwidth bus technology is designed to work in concert with the high-performance processing power of the Pentium II processor.

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What is AGP?

Please see the VGA Card section.

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