1. Field of the Invention
The present invention relates to computer system memories and, more particularly, to controlling operating voltage provided to memory devices.
2. State of the Art
Computer systems are typically designed to accommodate memory devices that perform within a specific band of operational parameters. For example, a computer design may accommodate specific memory devices that perform reading and writing operations at a defined speed or rate. Such an interdependent design philosophy disregards many realities of the environment of a computer system over its lifetime. For example, designing for a specific performance relationship between a microprocessor and memory devices does not allow for the independent improvements to each of the components that may, and generally does, occur. For example, microprocessor speeds may outpace memory device performance, or vice versa. In an attempt to decouple such a relationship, memory controllers have been designed to provide data brokering between the microprocessor and the memory device. Once memory controllers became ubiquitous in computer system designs, broad variations in memory device performance parameters have become commonplace.
Additionally, memory devices are generally tested and graded during manufacturing, with similarly performing devices integrated together into independent memory modules. As technology advances or as a computer system's memory needs change, memory modules may be upgraded or exchanged within a computer system. When memory modules are added, replaced, or exchanged with other memory modules, the memory controller adapts the timing between the memory modules and the microprocessor.
To date, the adaptation between the memory modules and the memory controller has been limited to modifications in timing and control parameters. However, it is known that memory technology improvements have also been made which have resulted in changes to improved or optimal operational voltages of the memory devices. Memory devices operating at a modified voltage level may exhibit an improvement in performance. Adaptation of such parameters has not been addressed by the prior art.