Board:via/epia: Difference between revisions

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==Current problems==
==Current problems==
* MA map type is set incorrectly for some types of DIMM. Patch available.
* MA map type is set incorrectly for some types of DIMM. Patch available.
* some memory errors persist even once the MA map type is set correctly; This may be caused by LB passing an incorrect e820 memory mapThis conclusion is based on memtest86 passing all tests when "Probed" is selected for memory sizing, but failing when "BIOS-Std" or "BIOS-All" is selected.
* Mixing of memory widths appears to cause memory errors.  The 256MB and 64MB DIMM from the table below show memory errors when installed together.
* shutting down system does not turn off power.
* shutting down system does not turn off power.


==MA Map Types==
==MA Map Types==
The values for MA map type refer to bits 15-13, 7-5, and 3-1 of offset 0x59-0x58 of the VT8601A host bridge.  See the VT8601/PLE133 data sheet for details.  All values other than 0xx and 100 are documented as "reserved (do not program)"
The values for MA map type refer to bits 15-13, 7-5, and 3-1 of offset 0x59-0x58 of the VT8601A host bridge.  See the VT8601/PLE133 data sheet for details.  All values other than 0xx and 100 are documented as "reserved (do not program)"
{| border="1"
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|+ Values determined by testing various modules with the factory BIOS.
|+ Values determined by testing various modules with the factory BIOS.

Revision as of 00:32, 10 May 2007

Current problems

  • MA map type is set incorrectly for some types of DIMM. Patch available.
  • Mixing of memory widths appears to cause memory errors. The 256MB and 64MB DIMM from the table below show memory errors when installed together.
  • shutting down system does not turn off power.

MA Map Types

The values for MA map type refer to bits 15-13, 7-5, and 3-1 of offset 0x59-0x58 of the VT8601A host bridge. See the VT8601/PLE133 data sheet for details. All values other than 0xx and 100 are documented as "reserved (do not program)"


Values determined by testing various modules with the factory BIOS.
DIMM size Row Density (SPD 31) Width (SPD 13) Rows(SPD 5) MA map type
512MB 256MB 8 2 0xe (111)
256MB 128MB 16 2 0xc (110)
128MB 128MB 16 1 0xc (110)
128MB 64MB 8 2 0x8 (100)
64MB 64MB 8 1 0x8 (100)