Intel SC450NX - Server Platform - 0 MB RAM, Product Manual

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Video
The onboard, integrated Cirrus Logic CL-GD5480 64-bit VGA chip contains an SVGA controller
that is fully compatible with these video standards: CGA
†
, EGA
†
, Hercules
†
Graphics, MDA
†
, and
VGA. The standard system configuration comes with 2 MB of 10 ns onboard video memory. The
video controller supports pixel resolutions of up to 1600 x 1200 and up to 16.7 M colors.
The SVGA controller supports analog VGA monitors (single and multiple frequency, interlaced
and noninterlaced) with a maximum vertical retrace noninterlaced frequency of 100 Hz.
You can not add video memory to this system. Depending on the environment, the controller
displays up to 16.7 M colors in some video resolutions. It also provides hardware-accelerated bit
block transfers (BITBLT) of data.
SCSI Controller
The baseboard includes two SCSI controllers. A narrow SCSI controller (SYM53C810AE) is on
the PCI-A bus, and a dual-channel wide LVD/SE (Ultra2/Ultra) SCSI controller (SYM53C896) is
on the PCI-B bus. The narrow provides support for the legacy 8-bit SCSI devices in the 5.25-inch
drive bays. The wide drives one SCSI backplane and provides support for external expansion.
Internally, each wide channel is identical, capable of operations using either 8- or 16-bit SCSI
providing 10 MB/sec (Fast-10) or 20 MB/sec (Fast-20) throughput, or 20 MB/sec (Ultra),
40 MB/sec (Ultra-wide) or 80 MB/sec (40 Mhz) (Ultra-2).
The SYM53C810AE (narrow) contains a high-performance SCSI core capable of Fast 8-bit SCSI
transfers in single-ended mode. It provides programmable active negation, PCI zero wait-state
bursts of faster than 110 MB/sec at 33 MHz, and SCSI transfer rates from 5 to 10 MB/sec. The
narrow SCSI comes in a 100-pin rectangular plastic quad flat pack (PQFP) and provides an “AND
tree” structure for testing component connectivity.
The Sym53C896 (wide) contains a high-performance SCSI bus interface. It supports SE mode
with 8-bit (10 or 20 MB/sec) or 16-bit (20 or 40 MB/sec) transfers and LVD mode with
8-bit (40 MB/sec) or 16-bit (80 MB/sec) transfers in a 329-pin ball grid array (BGA) package.
Each controller has its own set of PCI configuration registers and SCSI I/O registers. As a
PCI 2.1 bus master, the SYM53C896 supports burst data transfers on PCI up to the maximum rate
of 132 MB/sec using on-chip buffers.
In the internal bay, the system supports up to six one-inch SCSI hard disk drives, plus, in the
5.25-inch removable media bays, three SCSI or IDE devices (the controller itself supports more
devices, but the 5.25-inch bay can contain a maximum of three devices). A wide SCSI cable
provides two connectors for Ultra SCSI devices (one of these connectors is for the optional SCSI
backplane, if your system has that). However, SCSI devices do not need to operate at the ultra
transfer rate. All drives on the bus must be Ultra-2 (LVD) to run at 80MB/sec (40Mhz). The 5,
10, and 20Mhz operations can coexist on the bus and each device will interact at its appropriate
speed.
No logic, termination, or resistor loads are required to connect devices to the SCSI controller other
than termination in the device at the end of the cable. The SCSI bus is terminated on the baseboard
with active terminators that can be disabled.