upgrading RAM

[Hugbees]

I heard for a computer to read RAM, all the sticks must be of equal value. I want to upgrade to another gig of ram, and was thinking of buying a 2gig stick and replacing one of my two 1gig sticks.

Can I do that, have a 2gig and a 1gig stick? Or will I need to get 2 2gig sticks? I heard iMacs can only support 3gig of ram tops, but I'm not sure if you still need to get 2 2gig sticks for it to work.

 

[rdowty]

I heard for a computer to read RAM, all the sticks must be of equal value. I want to upgrade to another gig of ram, and was thinking of buying a 2gig stick and replacing one of my two 1gig sticks.

Can I do that, have a 2gig and a 1gig stick? Or will I need to get 2 2gig sticks? I heard iMacs can only support 3gig of ram tops, but I'm not sure if you still need to get 2 2gig sticks for it to work.

I know if you want to go to 6GB you have to do a 2GB and 4GB stick so at least it's possible to use mismatched pairs. I'm not sure if there's any performance hit.

 

[ChrisA]

I know if you want to go to 6GB you have to do a 2GB and 4GB stick so at least it's possible to use mismatched pairs. I'm not sure if there's any performance hit.

Certainly, you can use non-matched pairs. But if the computer "sees" that they are matched it can switch into a mode that reads from both sticks at ones and is faster

In the current line of mac computers, yes you take a very slight performance hit for non-match RAM. I think it's on the order of around 10% But depending on what you are doing with the computer you gain a lot of performance from the extra RAM.

If you are just doing web surfing, email and so on then 4GB done with matched RAM is good. But if you are doing work that can take advantage of the extra RAM then go for it. Some kinds of video editing and it you run VMware Fusion the RAM helps but if the RAM is not used having more of it no help

 

[yippy]

That is simply not true. You can put a 2GB +1GB sticks in an iMac and it will work just fine. As for how much they can support, it depends on when the iMac was made, the newer the iMac, the more RAM it can support. However, most can support 3Gb.

Where that misconception comes from is that there is a slight performance boost if both sticks are the same.

The other place it comes from is that in the Mac Pro, and only the Mac Pro, you do have to install RAM in pairs of identical sticks of ram. But you have an iMac so you don't need to worry about that.

 

[~Shard~]

You might find some useful information in our RAM Guides.