ok so i have 2 gig ram in my computer 2ex 1 gigs (800 MHz) and i wanna buy another one so i have 3.. my motherboard has 4 slots for ram but some guy told me something about them working in dual :S didn't really know what he was saying anyways i wonder if i can get another pair of the same ram so i have 3 of them (3gig) or do i need to buy 2 more 1 gigs.. so i have 4 gig?? so they work in dual whatever that is ...
That "some guy" was telling you that if you only added 1GB of RAM to your setup, you wouldn't be able to run your memory in dual-channel mode. That mode requires two/even number of the same memory sticks, and provides better performance because it allows your RAM to run in tandem.
The kind of memory you need to enable dual-mode really depends on your motherboard however, so barring asking the guy another question, check your mobo manual.
ok i see then.. but can you determinate if i can use 3 ex ram's or will they all work in single channel?... and i want to ask if i can buy 1 2gig also 800mhz so i have 4 gig... 2 1gig's and 1 2gig... this is my motherboard if it may help M2N68-VM (ASUS)
Okay, in great detail.
Memory is arranged in "banks". See your 4 slots? 2 of them are Bank 1, and 2 of them are Bank 2. Sometimes they are referred to as "Bank 0" and "Bank 1".
Now, on a modern motherboard, it can run in what is called "dual channel mode" which effectively doubles the data bus width to the "bank" of memory. But each "bank" must have 2 sticks installed, and they must be identical.
If you only put in 1 stick in a bank, you can not have dual operation.
If you put 2 sticks in a bank, and they are different sizes, you cannot have dual channel operation.
If you have 2 identical sticks in 1 Bank, and only 1 stick in the other Bank, you cannot have dual channel operation.
Understand? You must install memory in pairs to be able to make use of dual channel. Your memory will work doing what you have outlined in your last post, but it will not be running in dual channel mode. Dual channel mode does not make a huge difference, but it does help. When you buy memory, you might as well buy it and install in the configuration that makes the most sense, and give you the best performance.
So buy another 2 sticks of 1 gig each, giving you a total of 4 gig , running in dual channel mode. Try to buy the same memory you already have. If you cannot get exactly the same memory you have, make sure you at least buy memory that operates at the same voltage of the memory you have.