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I have a 1 GB DDR2 667 MHz RAM

installed into my system

can i use 2 GB DDR2 800 MHz RAM

along with the existing RAM

is there any problem if i use both in different slots simultaneously


shall i remove the previous RAM.

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marked as duplicate by bwDraco, Carl B, AthomSfere, Mokubai, Tog Nov 10 '13 at 13:01

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Note that due to the the uneven size configuration, your ram will only run in single channel mode. this means that your speeds will be effectively halved. you may want to try both with and without the original ram to see if which you prefer. – Frank Thomas Nov 9 '13 at 22:47
@FrankThomas if this is an Intel system then it can run in a flexible dual-channel mode where some of the memory is dual channel and some is single channel. It's not optimal, but is possibly better than not at all. – Mokubai Nov 10 '13 at 10:31
@Mokubai Yes it is a Intel System Thanks for your response coz i was confused between Frank's and AthomSfere's answers – Anonymous Mohit Nov 10 '13 at 11:22
Just so that you know I have voted to close as this is a duplicate of the linked answers in the comments but the answer you are looking for is essentially "There should be no problem using memory of different speeds together so long as they are of the same type (DDR2 with DDR2 and so on). The main problem with different speed memory is that the faster memory will work at the speed of the slower memory and so you will not see the benefit of the faster memory. The caveat is than now you will have a partial dual-channel configuration where some memory will be much faster and some will not." – Mokubai Nov 10 '13 at 11:38
You also already have a single channel configuration so @FrankThomas' comment does not really apply, you will be going from a 1GB single channel configuration at 667MHz to a 3GB flexi-dual channel (2GB dual /1GB single) configuration at 667MHz so 2GB of your memory will be much faster while you will see no change in speed for the final 1GB. Computers are fun... – Mokubai Nov 10 '13 at 11:55

1 Answer 1

It should work just fine. The faster RAM will down-clock to the slower speed. 3GB is substantially better than 1GB or even 2GB.

You will notice a difference using 3GB, the slower speed will only real show a difference in benchmarks, but even at that more is more important than faster alone.

Lastly, that second stick is certainly not rated for 8 Ghz (8000 Mhz).

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oops! i have updated it is 800MHz – Anonymous Mohit Nov 9 '13 at 20:49

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