DIGITAL has announced the most expandable PC platform in the industry, the DECpc XL series. The new series offers unparalleled investment protection with state-of-the-art PCI bus technology, a choice between i486 and Pentium microprocessors, and the ability to upgrade to future i486, Pentium and Alpha AXP technology. It also offers users the ultimate in subsystem choice, including CISC or RISC microprocessor platforms, high performance graphics cards, concurrent PCI bus peripherals, and a range of high-capacity hard drives. At the heart of Digital's DECpc XL system design is the Peripheral Component Interconnect (PCI) local bus architecture. The new series uses a motherboard/daughtercard design in which CPU-specific components reside on the daughtercard, and common system components are contained on the motherboard. Alan McMillan, director of Digital Asia's PC business unit, said: ''This new series represents both the hottest performance on the market today, as well as an engineering breakthrough that allows today's user to upgrade within the Intel line or to convert to Alpha AXP technology when ready. This is true investment protection.'' The new series comprises four system models - DECpc XL 433dx, DECpc XL 466d2, DECpc XL 560, and DECpc XL 566 - offering users a choice of the highest performing i486 processor or state-of-the-art Pentium processors. Pentium 60 megaHertz (MHz) and 66MHz daughtercard upgrades, as well as a future Alpha AXP daughtercard upgrade, are available as customers' performance requirements increase. A highly integrated local bus architecture, PCI is optimised to take advantage of today's available microprocessor and personal computer technology. It ensures reliable operation between components, add-in cards and systems, while maintaining compatibility with today's ISA/EISA/MicroChannel expansion buses. With PCI technology available, users of Intel's i486 or Pentium processor, or Digital's Alpha AXP processor, can derive the full benefit of faster CPU speeds through interchangeable daughtercards. Powerful graphics programs, multimedia applications and networking can run independently, thereby avoiding bus bottlenecks. The PCI specification has been developed with an eye to the future. It supports a multiplexed 64-bit data and address bus for the emerging wave of high-performance peripherals that require a wide data path. This 64-bit extension of PCI's 32-bit data and address buses can double the system's overall bus band width to 264 megabits per second (Mbps). All communications between 32 and 64-bit CPUs and peripherals are transparent to users. The complete DECpc XL design centre consists of the following: PCI/ISA main logic board (MLB), choice of PCI graphics controllers, standard SCSI dual speed CD-ROM, integrated PCI local bus SCSI-II, up to 192 megabytes (MB) of memory on the MLB, customer upgradable flash BIOS, five bays (one internal, four external), six slots (two PCI, three ISA, one interleaved), and a 300 Watt/five Volt and 3.3 Volt power supply, in Digital's easy access, micro-tower enclosure.