Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

On the specs of a computer I saw, it said the CPU speed was 2.something Gigahertz, but the RAM speed was 1300MHz (1.3GHz). That does not make sense, why would the RAM be slower than the CPU? You could never use the full speed of the CPU, could you? Somebody, please explain. I'm stumped with this one.

Any information would be appreciated.

share|improve this question
You can't equate clockspeeds in this manner...I think properly explaining this may be beyond the scope of a short answer, though. Suffice to say that the memory clock is independent (and for most computers you'll see in a store, it's rare to see anything but 1066, 1333, or 1600MHz right now). – Shinrai Jan 9 '13 at 19:16
Please read this – Lorenzo Von Matterhorn Jan 9 '13 at 19:18
This is precisely why computer scientists freak out about cache misses. – Mehrdad Jan 9 '13 at 19:21
up vote 7 down vote accepted

tl;dr You're fine, you can fully utilize your processor and you will not have any troubles with performance. A new motherboard/ram is not required.

CPUs have a cache on them, this is where all data access takes place. If there is data that is in memory but not in the cache, it has to be loaded into the cache first.

The speed of the ram has less to do with how long it takes to access it than the memory timings do. These timing specify exactly how many cycles it takes to access the RAM. You can see this Wikipedia Article for details about memory timings.

As Far as your CPU is concerned, it actually has a internal clock speed much less than 2 GHz, what gives you the 2 GHz effective clock speed is the CPU Multiplier. As long as your base clock speed is less than the speed for your ram, you're fine. For example, my i5 2500k runs at 3.6GHz, its base clock speed is 100hz, and its multiplier is 36.

Another thing to be aware of, is that your ram isn't actually running at 1600hz, is running at 200hz. You can get a table of that info here. But as I said above, that 200hz is higher than the base clock speed of 100hz, so even on a good processor like my i5, 200hz is more than enough speed.

share|improve this answer
This is pretty good summary, and so I will upvote it. (I still think a really proper discussion of this requires some really in-depth research, but this does well for its scope.) – Shinrai Jan 9 '13 at 20:33

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .