Adding memory and bus cards

32-bit memory

It is strongly recommended that you use 32-bit memory approved by your machine manufacturer. Using 16-bit memory instead will degrade overall machine performance.

NOTE: Certain manufacturers reserve the upper 384KB of the first megabyte for DOS. On some machines, this ``shadow'' RAM cannot be accessed by SCO OpenServer systems. You may need to install additional memory to run SCO OpenServer. If possible, ``BIOS shadowing'' and ``video shadowing'' should be disabled.

If you see one of the following messages:

FATAL: parity error on the Motherboard

FATAL: parity error on add-on card

PANIC: Parity error address unknown

PANIC: Parity error at address 0xxxxxx

some part of your hardware is sending a ``non-maskable interrupt'' (a signal sent by the hardware that halts the operating system). The precise message will depend on your particular system. You should run your system's hardware diagnostics tests, if available. In addition, physically reseat your memory cards, SIMMs, or individual memory chips, checking for bent pins. If these measures fail to correct the problem (or you do not feel comfortable in checking your hardware yourself), seek professional hardware support.