Do RAM speeds actually matter?

[Wholesalespy52]

So, I woke up wondering this today. Does RAM speed actually matter to system performance? Like for example if I got a kit of 4 gigabytes of 1333 RAM would it actually be significantly different from a 1600 megahertz, 1866 megahertz or even 3200 megahertz RAM?

And if they don't actually matter then at what point do they start to matter?

 

[Tradesman1]

Depends on what you do, in gaming faster DRAM has shown increases of up to 10% in game performance, depending on the game. As more developers utilize DRAM better that may well grow. In regular system use, having faster DRAM (and more of it) show even more when multi-tasking and/or using memory centric apps. Wrote an article that might be interesting here:

http://www.tomshardware.com/reviews/dram-benchmark-fluctuations,4080.html