d.Observe the LEDs and refer to the following table.

 

Green

Yellow

 

Power LED

diagnostic LED

diagnostic LED

Action

 

 

 

 

ON

ON

OFF

This is the normal condition of the LEDs when the power is

 

 

 

OK.

 

 

 

 

OFF

OFF

OFF

Make sure the power cord is attached to a working electrical

 

 

 

outlet.

 

 

 

If the electrical outlet is OK, replace the power supply.

 

 

 

 

OFF (after the

ON

OFF

Replace the system board

power button

 

 

 

has been

 

 

 

pressed)

 

 

 

 

 

 

 

ON

ON

ON

Replace the power supply

 

 

 

 

If the Diagnostic LEDs are in the normal condition and the problem persists, replace the system board and the microprocessor, one at a time, until the computer works correctly.

8.Run the Diagnostic programs. See Chapter 5, “Diagnostics using PC-Doctor for DOS,” on page 47.

v If you receive an error, replace the part that the diagnostic program calls out or go to “Diagnostic error codes” on page 59.

vIf the test stops and you cannot continue, replace the last device tested.

Problem determination tips

Due to the variety of hardware and software combinations that can be encountered, use the following information to assist you in problem determination. If possible, have this information available when requesting assistance from Service Support and Engineering functions.

vMachine type and model

vProcessor or hard disk upgrades

vFailure symptom

Do diagnostics indicate a failure?

What, when, where, single, or multiple systems?

Is the failure repeatable?

Has this configuration ever worked?

If it has been working, what changes were made prior to it failing?

Is this the original reported failure?

vDiagnostics version

Type and version level

vHardware configuration

Print (print screen) configuration currently in use

BIOS level

vOperating system software

Type and version level

Note: To eliminate confusion, identical systems are considered identical only if they:

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Lenovo 8088, 8094, 8089, 8090, 8087, 8086 manual Problem determination tips, Green Yellow Power LED Diagnostic LED Action

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.