ISA-based devices remain as the most troubling area for support issues related to PC configuration. The most common causes for PC customer support calls are resource conflicts or loss of functionality occurring when end users install ISA devices such as modems, audio, or multimedia devices.
To reduce the barriers to satisfactory user experience and to reduce the cost of customer support, designers must migrate away from incorporating ISA devices in PC systems designed for Windows 98 and Windows NT. Therefore, the most dramatic PC 98 requirements emphasize the movement away from dependency on ISA and other legacy devices.
Although these requirements might seem radical, the discussion of migration is not new. In fact, migration away from legacy devices is a fundamental issue for all hardware guidelines, beginning with the migration toward Plug and Play devices.
Processor performance has improved steadily since the ISA bus was first defined; today’s processor is executing more than 300 times faster than the original PC. Even with the advanced multitasking implementations of the Windows family of operating systems, there is still a performance impact when a very fast processor has to access a relatively slow bus such as ISA. Hardware migration away from ISA, coupled with improved software techniques, will result in an improved user experience.
Every system and device manufacturer is aware of the support burden related to configuration issues for legacy devices. Often, when users add new systems to their PCs, they upset the delicate balance of system resources assigned to accommodate a collection of ISA and proprietary device implementations. These users think they are simply installing a new application or a new modem, but they lose functionality elsewhere in their systems and only have customer support to turn to in resolving the resulting problems.
To improve system performance, reduce customer support costs, and ensure true ease of use in PC systems and peripherals, manufacturers must plan to migrate all components in their systems away from ISA and legacy devices.
Of course, this migration has to be undertaken on a step-by-step basis. The first step is elimination of non-Plug and Play devices from new systems. With the addition of ACPI support and Zero Administration features in the Windows 98 and Windows NT operating systems, Microsoft is providing a foundation in the operating system for configuration, power management, and central administration of systems and devices.
Intel and Microsoft are aware that most system-board designs for 1998 include the ISA bus, and that COM and LPT ports will be included in systems for legacy device support. However, under the PC 98 guidelines, the system must not ship with add-on devices that use these ports or the ISA bus. The ultimate goal for future designs is the complete elimination of the ISA bus.
The following list summarizes the planned migration road map:
For Entertainment PC 98, the requirement is the same as for Network PC: No ISA expansion slots shall be exposed for end-user access.
PC 98 allows OEMs to continue to provide legacy mouse devices and keyboards, but encourages use of USB solutions. Legacy and proprietary solutions for game devices are not compliant with PC 98 requirements.