Compaq 164SX User Manual

Page 62

5–6

Upgrading the AlphaPC 164SX

Increasing Microprocessor Speed

Attach the microprocessor heat sink. The heat-sink material is clear
anodized, hot-water-sealed, 6061-T6 aluminum. The nut material is 2011-T3
aluminum (this grade is critical). Perform the following steps to attach the
heat sink:

1. Observe antistatic precautions.

2. Align the heat-sink holes with the threaded studs on the ceramic package.

3. Handle the heat sink by the edges and lower it onto the chip package,

taking care not to damage the stud threads.

4. Set a calibrated torque driver to 15 in-lb, ±2 in-lb, (2.3 Nm, ±0.2 Nm).

The torque driver should have a mounted 3/8-inch socket.

5. Insert a nut into the 3/8-inch socket, place on one of the studs, and tighten

to the specified torque. Repeat for the second nut.

6. If the sink/chip/fan clip is used, properly install it by positioning it over

the assembly and hooking its ends around the ZIF socket retainers.

Attach the heat-sink fan assembly:

1. Place the fan assembly on top of the heat sink, aligning the fan mounting

holes with the corresponding threaded heat-sink holes. Align the fan so
that the fan power/sensor wires exit the fan closest to connector J14 (see
Figure 2–1). Fan airflow must be directed into the heat sink (fan label fac-
ing down toward the heat sink).

2. Using a calibrated torque driver set to 3 in-lb, ±1 in-lb, secure the fan to

the heat sink with four 6–32 × 0.625-inch screws.

3. Plug the fan power/sensor cable into connector J14.

Note:

When installing the microprocessor, you must change the frequency of
its clock output by setting the system clock divisor switches, as
described in Section 2.2.