Apple Event: May 7th at 7 am PT
Hello every one,
I've been struggling to find a definate answer to this. I have a new iMac with 4GB of RAM (2x2GB)
I have added another 8GB (2x4GB) in the system profiler it now shows this:
Does this mean I have mis-matched pairs?
i.e should it be the Banks or the Dimms that are matched??
Many Thanks
Rob
iMac, iOS 4.3.2
It is wise to match the pairs. Put the 2 x 2 DIMMS in Bank 0 and the others in Bank 1.
You answered my question twice thank you!
I'm not sure why Apple don't mention this on the instructions, as out of the factory there is one DIMM installed in each Bank. Therefore, to pair the memory properly you have to re-seat one of the factory installed DIMMs rather than just add new memory (if adding 4GB sticks).
I shall re-seat the RAM and report back 🙂
Rob
Your welcome.
It now looks like the screen shot below.
Obviously it's worked in both configurations, and both ways displayed 12GB RAM installed, but I also thought it should be the banks that are paired to enable the best performance. I'm not sure whether or not it will be noticable to the human eye but it's always better to have these things correctly setup 🙂
It doesn't really matter then, as long as you have 12GB that is what matters. AFAIK as long as the system indicates the correct amount of RAM performance (in your case 12GB) performance will be the same. Bottom line, time to forget about it and begin enjoying your computer!
Already loving it, just trying to get my head around all the different shortcut keys ! and how to get out of iPhoto when it crashes in full screen mode! - but that's for a different thread haha
Is this your first Mac?
rkaufmann87 wrote:
It is wise to match the pairs. Put the 2 x 2 DIMMS in Bank 0 and the others in Bank 1.
Roger, I disagree with putting 2x2GB in the same bank and 2x4GB in the other bank. That’s not what is meant by pairing the memory modules. You want to install memory according to the directions in the manual for the computer. It clearly says to install new memory in the empty slots. If you are replacing the original memory, it clearly says to install that memory in the two slots furthest from the dispaly, which means one module in bank 0 and one module in bank 1.
The memory modules are paired (installing the same size in each bank) in order to support dual-path access to the memory in the iMac. If you mismatch the sizes of the memory modules, the memory will work but only with single-path access.
So Rick,
you're saying that each pair is made of two banks? as in my original configuration.
In answer to rkaufmann87, this is my first Mac so I'm obviously not used to the memory layout. Im used to seeing slots layed out in pairs across a mother board so it's easier to see how to pair them up.
I was going by the fact the instructions had assumed the user was adding identical memory to the factory installed stuff so pairing wasn't so important. I did ask AppleCare but they didn't know.
Anyone out there that has 12GB factory installed that can post a shot of their System Profiler please?
Seeing that this is your first Mac then I'd recommend bookmarking and visiting the following sites. They're designed for folks like yourself that have made the switch from PCs. There is a lot to learn however transitioning from a PC for most people is usually fairly easy.
and if you like to use Keyboard Shortcuts: Keyboard Shortcuts
Thanks! I'll certainly have a read and keep those handy!
Rather then a switch it's more of a merge haha. Most of my business apps are Windows only, so I'm running VMWare Fusion with Windows 7 in unity mode! - hence the RAM upgrade.
I'm running both operating systems concurrently and it's working like a dream as I now get the best of both worlds. I'm also having the One 2 One lessons at the Apple Store which are amazing for what they cost. I've only had the machine 5 days now so i'm learning fast 🙂
Globalnet wrote:
So Rick,
you're saying that each pair is made of two banks? as in my original configuration.
I was going by the fact the instructions had assumed the user was adding identical memory to the factory installed stuff so pairing wasn't so important. I did ask AppleCare but they didn't know.
Yes, follow the instructions in the manual as it’s right (at least this time). Too bad the manual doesn’t tell you why to do this. But I researched how the memory is accessed (single versus dual) on the Intel site when I first got my iMac and was comparing it to the Mac Pro that supports up to triple path access.
Anyone out there that has 12GB factory installed that can post a shot of their System Profiler please?
Here it is:
You need to have the 2 x 2 next to each other at the top (the top as you see it when the iMac is lying screen down with the slots facing you). That is how mine were from the factory. You then install the 2 x 4 in the two bottom slots next to each other. Your current configuration may work, but it's better to match them side to side.
And this is what the top window should look like:
Yes.
Do I need to match up Banks or the Dimms in new iMac
