1-12 System Overview
SCSI Controller
The system board includes an embedded dual Symbios Logic SYM53C875, PCI SCSI
host adapter. The SYM53C875 contains two independent SCSI controllers that share a
single PCI bus master interface. Internally, each controller is identical, capable of
operations using either 8- or 16-bit SCSI providing 10 MB/s (Fast-10) or 20 MB/s
(Fast-20) throughput, or 20 MB/s (Ultra) or 40 MB/s (Ultra-wide) throughput. As
implemented on the system board, controller A attaches to an Ultra-2 SCSI backplane
that supports up to seven Ultra-2 SCA drives. Controller B may be used to support
SCSI devices in the removable media bays.
Video Controller
The system has a high-performance SVGA subsystem that supports the following:
! BIOS compatibility with VGA, EGA, CGA, Hercules Graphics, and MDA
! 2 MB of Video Random Access Memory (VRAM) video buffer
! 16-bit bus for high-speed display memory access
! Hardware accelerated bit block transfers (BITBLT)
! Display power management system
! Supports 72Hz refresh, non-interlaced at: 640x480, 800x600, 1024x768, or
1280x1024 resolutions
! Displays of up to 16M colors at 640x480 and 800x600 resolutions, 64K colors at
1024x768 resolutions and 256 colors at 1280x1024 resolutions.