I've recently bought a new laptop with 8GB of RAM in it. It has 4 slots inside so I want to put the RAM from my old laptop in it as well. However, they have different frequencies. So if I put the old RAM in there as well, would it have any adverse effects on the system?
11 Answer
Theoretically it's fine. Just make sure it has the same configuration (i.e. number of pins, size/design). This is very important for laptops.
Generally the faster RAM will be automatically 'underclocked' to achieve effectively the same speeds. You could attempt to overclock the slower RAM, but I honestly can't see there being much of an increase in performance.
It is recommended to have a pair of identical RAM sticks just for 100% compatibility, but as long as they are compatible, with specifications being mostly the same, it shouldn't be a big deal.
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