4825 SX  (250-5141/42)           Video Memory           Faxback Doc. # 1691

To increase the amount of video memory from 512KB to 1024KB (1MB), you can 
install an optional video memory upgrade kit on the main logic board. Order 
two Cat. # 25-1082A Video Memory Upgrade Kit from your Radio Shack Store.
This kit contains two 256KB x 4, 70ns DIP DRAM chips.

The 256-color, 1024 x 768 and 256-color, 800 x 600 graphics modes require 1MB 
of video memory.

CAUTION: Static electricity can damage electronic components in a computer. 
Before opening the computer, discharge any accumulated static electricity from 
yourself by touching a grounded metal object.

1. Turn off the computer, and disconnect all cables.

2. Open the computer. Refer to "Main Logic Board Layout" to locate the video 
   memory sockets.

3. Remove a chip from the antistatic packaging.

4. Orient the chip so that the U shape on the chip aligns with the U shape on
   the socket.

   If the chip has no U-shaped marking, align Pin 1 of the chip with Pin 1 of
   the socket. Pin 1 of the chip is marked by a corner dot. Pin 1 of the
   socket is to the left of the U.

5. Carefully press the chip into the socket. Be sure that the pins of the chip
   do not bend.

6. Repeat Steps 3 through 5 to install the three remaining DRAM chips.

7. Set Switch 6 of SW1 to OFF to indicate that the computer now has 1024KB of
   video memory installed. Refer to "Main Logic Board Layout" to locate SW1.

8. Close the computer.