Sun Microsystems SPARCclassic Service Manual page 147

5. Remove the optional VSIMM (if present).
See "Removing the VSIMM" on page 113, for removal procedures.
6. Disconnect all cables attached to the main logic board.
For connector locations, refer to Figure 11–12 and Figure 11–13 in "Main Logic
Board" on page 124.
a. Disconnect the 12-pin power supply cable from its mating connector by
squeezing the clip at the end of the cable and pulling straight up.
b. Disconnect the keyboard soft power-on cable from its connector next to the
12-pin power supply connector.
c. Disconnect the LED/speaker cable from its mating connector on the main
logic board.
d. Disconnect the diskette drive data cable (if present) and the hard disk drive
data cable from their connectors at the front of the main logic board.
7. Remove the NVRAM chip.
See "Nonvolatile RAM (NVRAM)" on page 138, for details. Place the NVRAM
chip on the antistatic mat. Save the chip for installation on the replacement main
logic board.
8. Remove the main logic board.
a. Pull the MLB (main logic board) extractor lever toward the front of the
system unit to disconnect the main logic board from the system I/O board
(see Figure 11–15).
b. Raise the speaker assembly to allow removal of the main logic board
(see Figure 11–16).
c. Grasp the board by the SBus connectors with both hands. Tilt the board
slightly to avoid the speaker assembly and lift it up and out of the system
unit (see Figure 11–17). Avoid handling any of the delicate electronic
components or touching any of the circuit board traces.
d. Place the main logic board on an antistatic mat.
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