4 GB RAM showing up as 3, BIOS memory hole and all that

Daniel Rock freebsd at deadcafe.de
Sun Aug 21 16:56:20 GMT 2005

Martin Nilsson schrieb:
> The E stepping Opteron can remap memory. The earlier versions can't.

Also the earlier versions can remap memory, although different.

If I understand the documentation correctly:
(Document #26094: BIOS and Kernel Developer's Guide, Section 3.5.8)

on earlier models the memory can only be remapped between processor nodes, 
so if the first CPU has 4 GB (or more) memory attached, the memory hidden by 
the I/O space is lost.


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