COMPTIA A+ Practice Exam

DDR3 memory runs at what speed relative to the motherboard bus speed?

1. 2x

2. 3x

3. 4x

4. 5x

The correct answer is: 4x

DDR3 memory runs at 4 times the speed of the motherboard bus speed. This is because DDR stands for "double data rate", meaning it transfers data twice per clock cycle. So even though both the memory and motherboard bus have the same clock speed, the DDR3 memory can transfer four times as much data per clock cycle, making it effectively 4 times faster. Therefore, options A, B, and D (which are all less than 4x) are incorrect.