AMI Mark IV Screamer, Руководство пользователя

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Appendix A
Upgrading Cache Memory
The AMI 80386/80486 Mark IV Screamer motherboard Cache
memory system comes with a standard 64 KB of cache
memory. You can upgrade this to 256 KB by replacing the SRAM
in the Cache SRAM area on the motherboard.
Unpacking
The Cache SRAM are static sensitive devices and can be easily
damaged by electrostatic discharge.
Do not remove the chips from their protective anti-static bag
until you are ready to install them in the system. Unpacking
should be done on an anti-static mat grounded to a good earth
ground point. You should also be wearing an anti-static
wristband, grounded at the same point as the anti-static mat.
(An alternative is to use a sheet of conductive aluminum foil
grounded through a 1 Meg-ohm resistor to ground. Similarly, a
strip of conductive aluminum foil wrapped around the wrist and
grounded through a 1 Meg-ohm resistor will serve the purpose
of a wristband.)
Installing SRAM chips
Upgrading cache memory requires eight 64 KB x 4 20 ns and
three 64K x 4 17 ns SRAM chips.
Locate the Cache SRAM sockets that have 16 KB x 4 SRAM
chips. Using a chip removal tool or a small flat tipped
screwdriver, gently remove all chips. Do not remove the chip in
U52, located next to U53.
The 64 KB x 4 SRAMs will use the 2 rows that have 12 pins.
Carefully insert the 64 KB x 4 SRAM chips into the 12 pin rows
on the sockets. Insure that the notch etched on the
motherboard and the notch on the SRAMs are correct.