Which of the following is a key advantage of DDR3 over DDR2?

The choice indicating that DDR3 doubles the data transfer rate compared to DDR2 is correct because one of the primary advancements from DDR2 to DDR3 was in the increase of data transfer speeds. DDR2 typically operates at data rates starting from 400 MT/s (million transfers per second) to about 800 MT/s, whereas DDR3 starts from approximately 800 MT/s and can go up to 2133 MT/s and beyond. This enhancement in data transfer rate significantly improves the memory bandwidth, allowing for faster data processing, which is crucial for modern computing tasks and applications.

The other options are not accurate representations of the advantages of DDR3. For instance, DDR3 actually operates on a lower voltage compared to DDR2, reducing power consumption rather than requiring a higher voltage or increasing overall consumption. Furthermore, DDR3 does not have slower operational speeds; instead, it operates at higher speeds and is designed to address the increasing demands of applications in terms of both bandwidth and speed.