[an error occurred while processing this directive] Frequently Asked Questions for FreeBSD 2.X : Kernel Configuration : I have 128 MB of RAM but it seems that the system use only the first 64 MB. What's going on ?
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8.6. I have 128 MB of RAM but it seems that the system use only the first 64 MB. What's going on ?

Due to the manner in which FreeBSD gets the memory size from the BIOS, it can only detect 16 bits worth of Kbytes in size (65535 Kbytes = 64MB). If you have more than 64MB, FreeBSD will only see the first 64MB. To work around this problem, you need to use the kernel option specified below. There is a way to get complete memory information from the BIOS, but we don't have room in the bootblocks to do it. Someday when lack of room in the bootblocks is fixed, we'll use the extended BIOS functions to get the full memory information...but for now we're stuck with the kernel option.

            options "MAXMEM=<n>"
Where n is your memory in Kilobytes. For a 128 MB machine, you'd want to use 131072

Frequently Asked Questions for FreeBSD 2.X : Kernel Configuration : I have 128 MB of RAM but it seems that the system use only the first 64 MB. What's going on ?
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