Adding memory and bus cards

Disabled high memory on Corollary architectures

On Corollary EISA-based systems with ROM-Resident Diagnostics (RRD) prior to version 5.5, a problem can occur when you use the EISA configuration utility to enable the 15th megabyte address range as memory. The default behavior is for this memory range to be disabled. When this memory range is enabled the kernel attempts to map this memory twice resulting in the panic message:

   PANIC: smp_meminit - Adding overlapping memory segment 0x4f00000 - 0x5000000

If you have previously enabled this memory range through the EISA configuration utility, you can avoid the problem by disabling it before installing an SCO OpenServer system. This memory range is reclaimed after the machine is booted, so it still uses all the memory in the system. The problem can be permanently rectified by upgrading the RRD to the 5.5 version.