CAUTION:

Electrical current from power, telephone, and communication cables can be hazardous. To avoid personal injury or equipment damage, disconnect the attached power cords, telecommunication systems, networks, and modems before you open the server/workstation covers, unless instructed otherwise in the installation and configuration procedures.

Observe the following rules when working on electrical equipment.

Important: Use only approved tools and test equipment. Some hand tools have handles covered with a soft material that does not insulate you when working with live electrical currents.

Many customers have, near their equipment, rubber floor mats that contain small conductive fibers to decrease electrostatic discharges. Do not use this type of mat to protect yourself from electrical shock.

vFind the room emergency power-off (EPO) switch, disconnecting switch, or electrical outlet. If an electrical accident occurs, you can then operate the switch or unplug the power cord quickly.

vDo not work alone under hazardous conditions or near equipment that has hazardous voltages.

vDisconnect all power before:

Performing a mechanical inspection

Working near power supplies

Removing or installing main units

vBefore you start to work on the machine, unplug the power cord. If you cannot unplug it, ask the customer to power-off the wall box that supplies power to the machine and to lock the wall box in the off position.

vIf you need to work on a machine that has exposed electrical circuits, observe the following precautions:

Ensure that another person, familiar with the power-off controls, is near you.

Remember: Another person must be there to switch off the power, if necessary.

Use only one hand when working with powered-on electrical equipment; keep the other hand in your pocket or behind your back.

Remember: There must be a complete circuit to cause electrical shock. By observing the above rule, you may prevent a current from passing through your body.

When using testers, set the controls correctly and use the approved probe leads and accessories for that tester.

Stand on suitable rubber mats (obtained locally, if necessary) to insulate you from grounds such as metal floor strips and machine frames.

Observe the special safety precautions when you work with very high voltages; these instructions are in the safety sections of maintenance information. Use extreme care when measuring high voltages.

vRegularly inspect and maintain your electrical hand tools for safe operational condition.

vDo not use worn or broken tools and testers.

vNever assume that power has been disconnected from a circuit. First, check that it has been powered-off.

6Hardware Maintenance Manual

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Lenovo 8094, 8089, 8088, 8090, 8087, 8086 manual Hardware Maintenance Manual

8089, 8086, 8087, 8090, 8094 specifications

The Lenovo 8088, 8094, 8090, 8087, and 8086 series represent a significant portion of the historical legacy of computing, particularly in the realm of personal computers and microprocessors. Each of these models showcases unique features and technologies that contributed to the evolution of computing during their time.

Starting with the Lenovo 8088, this microprocessor was an enhancement of the earlier Intel 8086, designed primarily for use in IBM-compatible PCs. Its 16-bit processor architecture was notably capable of handling 8-bit data bus interactions, which made it more versatile for various applications. The 8088 had a maximum clock speed of 4.77 MHz, providing sufficient computational power for its time. One of the key features was its support for segmented memory, which allowed for more efficient memory management by dividing memory into segments for code, data, and stack.

The Lenovo 8094, while less commonly mentioned, often refers to IBM’s PS/2 line that utilized advanced features for the time. It supported VGA graphics, a significant improvement in visual output that opened new possibilities for graphical user interfaces. The 8094 also hosted a more sophisticated input/output system that allowed for better compatibility and connectivity with peripherals.

Moving to the Lenovo 8090, this model was part of the PS/2 portfolio, noted for its improved hardware architecture. It provided an upgraded interface for keyboard and mouse, which enhanced user interaction. With further support for high-density floppy disks and better memory access speeds, the 8090 paved the way for more efficient personal computing experiences.

The Lenovo 8087 was an auxiliary processor that brought floating-point arithmetic capabilities to the 8086 series. This coprocessor greatly expanded the computing power of the CPU by handling complex mathematical computations, which was especially useful in engineering and scientific applications. The 8087 allowed for more precise calculations than the basic integer math natively supported by earlier processors.

Finally, the Lenovo 8086, iconic in its own right, was a groundbreaking microprocessor that introduced the x86 architecture. It operated at clock speeds ranging from 5 to 10 MHz and was one of the first to support 16-bit data types fully. Its capabilities shaped software development and computer programming and established a foundation for the PC compatibles we know today.

In summary, the evolution from the Lenovo 8088 through to the 8086 helped shape modern computing paradigms by introducing features that improved performance, efficiency, and user experience, paving the way for the vast technological advancements seen in contemporary computing devices.