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

My laptop will soon be 6 years old. It's an ASUS Aspire 8930G and uses DDR3 memory modules. I need to replace the modules because they are faulty.

After opening up the computer and pulling out the modules to read the labels, it indicates:


I googled for replacement memory for this laptop and I've seen stuff on Amazon and eBay with numbers like:

PC3 10600

Doing some more search, I came to understand that this number difference has to do with the clock speed. The 8500S doesn't seem to exist much anymore. Probably was something when DDR3 initially came out. Nevertheless, the websites selling DDR3 seem to indicate that it is OK to use PC3 10600.

What isn't clear to me is what am I allowed to install in my laptop. Can I put in modules that are rated with a higher speed? What exactly does this clock speed mean? Does it mean it will operate up to that speed or does it mean that I MUST have that speed?

The last thing I want to end up doing is going into a store to buy some replacement DDR3 and only find out after plugging it in that it doesn't work because I failed to take something into account? Is there anything I should be aware of when getting the replacement memory?

share|improve this question
up vote 1 down vote accepted

FP/EDO/DDR memory modules can have a natural speed higher than the system speed; they will run at the slower speed, and this will not hurt them. Just make sure that you don't use higher-capacity modules than the system will allow.

share|improve this answer
Does this mean that my CPU/DDR3 automatically figure out what the maximum clock speed of the memory module is and adjusts itself accordingly? Or does this mean that the speed is fixed in my laptop and there is no adjustment? – AndroidDev Jun 25 '13 at 5:15
The system has a maximum speed which it can run at, which may be different from the memory's maximum speed. Both will run at the lower of the two. – Ignacio Vazquez-Abrams Jun 25 '13 at 5:17
@AndroidDev Just make sure you buy SODIMM/notebook/laptop RAM. Regular DIMM sticks won't fit in a laptop. Also, keep in mind that this often does not work the other way around, i.e. RAM can run at below its rated speed, but RAM rated lower than the system minimum won't run (the system clock cannot slow below a certain speed in most cases). – Bob Jun 25 '13 at 5:23

You must log in to answer this question.

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