RETAIN tip H167887: Whenever 4 GB (or more) of memory is installed, the BIOS displays the total size minus the amount of memory which is being reserved for the PCI, I/O, and other resources.
Source
RETAIN tip H167887
Symptom
Whenever 4 GB (or more) of memory is installed, the BIOS will display the total size minus the amount of memory which is being reserved for the PCI, I/O, and other resources.
Affected configurations
The system might be any of the following IBM eServer xSeries servers:
- xSeries 440, type 8687, any model
- xSeries 370, type 8681, any model
- xSeries 360, type 8686, any model
- xSeries 350, type 8682, any model
- xSeries 330, type 8654, any model
- xSeries 330, type 8675, any model
- xSeries 330, type 8674, any model
- xSeries 255, type 8685, any model
- xSeries 220, type 8646, any model
- xSeries 220, type 8645, any model
The system is any of the following IBM Netfinity servers:
- Netfinity 8500R server, type 8681, any model
- Netfinity 7000 M10 server, type 8680, any model
- Netfinity 5600 server, type 8664, any model
- Netfinity 5500 M20 server, type 8662, any model
The system is any of the following IBM IntelliStation servers:
- IntelliStation A Pro, type 6224, any model
- IntelliStation M Pro, type 6850, any model
Additional information
Each PCI device is allowed to claim some amount of memory resource. BIOS gathers the resource requirements of all the PCI devices installed and reserves the memory for the PCI devices.
If the memory size is less than 4 GB, BIOS will display the full amount of memory installed in the system. For any memory amount of 4 GB or greater, POST might display less than 4 GB of memory depending on what resources have been reserved for PCI devices. The amount of memory displayed will vary depending on the system and configuration.
When 4 GB or more of memory, physical or logical, is installed, some memory is reserved for various system resources and is unavailable to the operating system. The amount of memory that is reserved for system resources depends on the operating system, the configuration of the server, and the configured PCI options.
IntelliStation Pro:All operating systems listed
Older System x:Operating system independent / None
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