User`s guide

5.2 Environmental Requirements

The 21164 microprocessor is cooled by a small fan blowing directly into the

chip’s heat sink. The EB164 motherboard is designed to run efﬁciently using

only this fan. Additional fans may be necessary depending upon cabinetry and

I/O board requirements.

The EB164 is speciﬁed to run within the following environment:

Parameter Speciﬁcation

Operating temperature 10°C to 40°C (50°F to 104°F)

Storage temperature –55°C to 125°C (–67°F to 257°F)

Relative humidity 10% to 90% with maximum wet bulb temperature 28°C

(82°F) and minimum dew point 2°C (36°F)

Rate of (dry bulb)

temperature change

11°C/hour

2°C/hour (20°F/hour 4°F/hour)

5.3 Physical Board Parameters

The EB164 board consists of a 6-layer printed-wiring board (PWB) with

components mounted to side 1 only. The board is populated with integrated

circuit packages together with supporting active and passive components. The

EB164 is a standard, full-size PC AT board with the following dimensions:

• Width: 30.73 cm (12.10 in ±0.0005 in)

• Length: 33.15 cm (13.05 in ±0.0005 in)

• Height: 6.0 cm (2.375 in)

The board can be used in certain desktop and deskside systems that have

adequate clearance for the 21164 heat sink and fan. All ISA and PCI

expansion slots are usable in standard desktop or deskside enclosures.

Figure 5–1 shows the board and component outlines, and identiﬁes the major

components. Table 5–2 lists the components. Refer to Chapter 2 for jumper

and connector functions and locations.

5–2 Power and Environmental Requirements