Apple 640 manual Assigning RAM to the PC environment

Assigning RAM to the PC environment

The PC environment needs memory to operate. You can provide memory with a SIMM (Single Inline Memory Module) installed on the DOS- compatibility card in your computer, or by assigning RAM to the PC environment from your Macintosh. If a memory module is installed on the DOS-compatibility card, the RAM pop-up menu items in the PC Setup control panel will be dimmed (unavailable). The amount of memory available to the PC environment will depend on the amount of RAM on the installed memory module. See the Technical Information booklet to find out whether your DOS-compatibility card includes a memory module and what RAM capacity the memory module has. If a memory module is installed, skip to “Reinstalling PC Software,” next.

Memory installed on the DOS-compatibility card in your computer is for the exclusive use of the PC environment, and provides a marked improvement in performance of PC application programs.

If no memory module is installed, you need to assign RAM to the PC.

1Choose a memory size from the RAM pop-up menu in the PC Setup control panel.

If you’re installing DOS only, choose a minimum of 2 MB. If you intend to install Windows, choose a minimum of 4 MB.

Note: Windows performance will improve if you allocate more memory to the PC environment. However, RAM assigned to the PC environment is not available in the Mac OS until you turn off the PC environment in the PC Setup control panel and restart the computer.

2Restart the Macintosh.

IMPORTANT If the RAM size is set to 2 MB, modify the CONFIG.SYS file in DOS as follows:

DEVICE=C:\DOS\HIMEM.SYS /TESTMEM:OFF

Troubleshooting in the PC Environment 115