HP LTE Notebook PC 5250 Compaq Portable PC Card Support for Microsoft Windows - Page 4

WHITE PAPER (cont.) NOTE: Standby and hibernation are not fully supported when connected to a local area network or using a PC Card SCSI interface. Compaq recommends removing these types of devices from the PC card slots before entering either of these states. ... internal bus speeds that can be as much as four to six times faster than with 16-bit PC Cards in certain configurations. CardBus devices continue to use the same, well known, PC Card form factor and support many of the features that make PC Cards ideally suited to the portable platform such as hot swapping support. CardBus is not inherently supported by Windows NT 4.0, but is supported on Compaq portable platforms through CardWare® 5.0. CARDBUS FEATURES & BENEFITS Feature Benefit Uses PC Card form factor Provides the benefits of higher performance in the convenient form factor users have come to expect from the PC Card standard. Portable platforms with PC Card slots that are CardBus enabled also allow backward compatibility for 16-bit PC Cards. 3.3 volt power consumption Extends battery life in most configurations. 33MHz PCI Bus Provides up to 132MB per second peak transfer rates to support high performance peripherals such as 100Mbps Ethernet network interface cards and up to 40Mbps Ultra SCSI PC Card interfaces. Bus mastering capability Reduces processor overhead improving overall system performance. Table 2 - CardBus features & benefits summary Enhanced Power Management Standby and hibernation states are important power saving features portable users rely on to conserve battery power. Under Windows NT 4.0 PC Card devices are not able to respond to power management events such as entering standby mode. As such, power management functionality can lead to unexpected results when PC Cards are in use under native Windows NT 4.0. The way a particular PC Card behaves in response to power management events depends to a large extent on the direct enabler provided by the PC Card vendor. Contact your PC Card vendor directly for more information should you have a need to use a particular device without the benefit of CardWare® 5.0. Another key feature CardWare® 5.0 delivers is full support for the Advanced Power Management (APM) specification, version 1.2. PC Cards used in conjunction with CardWare® 5.0 operate more reliably when responding to power management events. The only notable exceptions to the power management support with PC Cards are local area networking (LAN) and SCSI interfaces. These types of devices typically do not support standby or hibernation modes with or without CardWare® 5.0. This limitation is not the result of any shortcoming in CardWare® 5.0, but rather lack of a widely accepted standard for developing power management-aware software drivers. The PCMCIA is an industry association responsible for developing PC Card standards. The Association recently ratified an addendum to the PC Card standard that defined a workable solution for to more reliable PC Card operation in response to power management events. This addendum, known as Proposition 187 - The NT Bindings Proposal is new and many PC Card vendors have yet to release updated software drivers that incorporate this latest addition to the PCMCIA specification. Customers who require the highest levels of reliability and performance on Compaq portable platforms should insist on PC Card vendors whose products have been designed to meet the PCMCIA specification. For more information on selecting PC Card solutions recommended by Compaq, refer to the section titled Compaq PC Card Solutions Program. 4