Not every motherboard will support every RAM speed. Older boards may be unable to run fast DIMMs at their full rated speed, while more recent models can refuse to boot if you use memory that's too slow.
But if you do splash out on super-fast RAM, what benefit can you expect to see? In theory, the fastest DIMMs can communicate with the CPU at more than twice the speed of slower modules. In practice, however, very few systems spend half their time waiting for RAM transfers, so expensive DIMMs won't magically double your performance.
To find out what difference RAM speed makes, we ran our standard benchmarks on a Vista system equipped with 4GB of DDR3-800, then repeated the test with 4GB of DDR3-1600 RAM.
For many applications, the performance advantage gained through faster RAM is nominal - dBpoweramp, Photoshop and 3ds Max gained no benefit at all, while the multi-applications test ran a mere 0.5% faster. But the benefit wasn't negligible: our Microsoft Office tests received a 1.5% boost, and the Canopus ProCoder video suite completed its tasks an impressive 5.5% more quickly. According to independent tests by our sister magazine Custom PC, games can receive a 2-4% boost. So if you use your PC for heavy gaming or entertainment, where every second counts, investing in the fastest RAM can pay off - just. You may even want to overclock your RAM.
But for everyday usage, RAM speed is almost a non-issue, and investing in faster DIMMs won't give a noticeable performance boost. You'll see far greater benefits from adding more RAM, or investing in a faster hard disk or CPU.
Next: Should I overclock my memoryBack to "Memory stripped bare"Author: Darien Graham-Smith
What are the benefits of buying extra speed?