Windows NT May Use a Different HAL Version for Some 486 CPUs (103933)

This article was previously published under Q103933

On some computers with older versions of the Intel 486 processor, Windows NT may use a different version of the Hardware Abstraction Layer (HAL); it may use HAL486C.DLL instead of HAL.DLL.

Intel identifies different versions of their processors with a letter designating the Stepping. The latest Stepping version of the 486 is D. If the Intel 486 processor with the C Stepping uses the standard HAL.DLL, there may be periodic system failures.

The correct HAL should be used based on the type of 486 processor installed in a computer. Setup installs HAL486C.DLL by default if it cannot confirm that the processor is a 486 with D or later Stepping.

In Windows NT, it is possible to determine the Steppings of a processor by doing the following:

1. From the File menu in Program Manager, choose Run, and then select WINMSD.EXE.
2. In Windows NT Diagnostics, choose Hardware, and then choose CPU Steppings.

The next dialog box identifies the Stepping version of CPU 0, which is the main processor.