American Megatrends 42 Series, User Manual

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Step 3 Install Coprocessor
The 80386 Mark V Baby Screamer motherboard supports the Weitek WTK3167, Intel 80387, and Cyrix™ 83D87 or other 387-
compatible coprocessors.
Choosing A Coprocessor
The coprocessor must operate at the same frequency as the system microprocessor. The following table lists math coprocessor
parts.
Board
Frequency Intel
Part No. Cyrix
Part No. Weitek Part No.
25 MHz 80387-25 83D87-25 WTK3167-025
33 MHz 80387-33 83D87-33 WTK3167-033
40 MHz None 83D87-40 None
Installing the WTK3167 on the Motherboard
U24 is the empty 121-pin PGA socket between the cache memory and microprocessor. The socket is labeled Weitek . Pin 1 of
the socket is near the chamfered edge of the socket. This corner corresponds to pin 1 of the Weitek also identified by a
chamfered edge ( on the bottom of the coprocessor ).
Check for bent pins on the coprocessor. Gently straighten any bent pins using a pair of pliers. Install the component into the
socket. Align the pins and press the Weitek coprocessor firmly into the socket, making sure that pin 1 of the Weitek
coprocessor is aligned with pin 1 of socket U24. See the following figure. Make sure that the Weitek coprocessor option in the
ADVANCED CMOS SETUP is enabled. The Weitek math coprocessor will not work unless it is enabled in AMIBIOS Setup. See
the ADVANCED CMOS SETUP Section on page .