MAC RAM performance

[Fzero]

A mate was looking into this issue on Macrumours, seemed to have a fair bit of conflicting arguments. I don't know the answer, so we both none the wiser.

Calling on you with the knowledge of memory [RAM] and the Apple Mac PC.

This might even be relating to the Intel chip even, not sure...

Basically, the Mac comes with 8GB RAM.

This is in the form of 2 x 4GB sticks.

There are 2 more empty banks in which more RAM could be inserted.

Have purchased 2 x 8GB sticks.

Question... Where should I stick them?

[cue: Up yer arse jokes ]

Jokes aside, I'd have thought it wouldn't matter, just dump them into the 2 empty banks.

Seems that there might be more to it though, and if using different sized RAM sticks, as in this case with the 4GB and 8GB ones, you should place them into respective banks.

Both 4GB ones into the 2 bank-0 slots.

Both 8GB ones into the 2 bank-1 slots.

If that was the case, as I've been reading, I would've expected Apple engineers to have done this from the factory, but that isn't the case, it comes out the box with one 4GB in the first 2 banks, bank-0 and bank-1.

From what I have read, some people say the performance would be improved fitting them this way, though only slightly, others say it doesn't matter at all and would make no difference.

I'm looking for the truth, so someone who has a great understanding of RAM probably/might know this.

I've tried to explain what I mean best as I can, this little image will hopefully add to that...

Spoiler

Anyone...?

cheers

 

[2bit]

Would you be able to go to an apple store and ask ?

 

[Fzero]

I could phone them I guess.

It was only that when Apple roll them out their shops, they place into one of the Bank-0 and one of the Bank-1 slots.

From that I would guess it wouldn't matter where you placed them, but then I've seen a lot of posts where others say it does make performance improvements depending on how you place it, albeit minor improvements.

I was just wondering, on the off chance someone here worked with RAM on a expert level and know for sure.

If you read the comments on here;

http://forums.macrumors.com/showthread.php?t=1229289

The posts before #15 mention about matching banks... post #15 confirms how Apple provide it out the box.

So you'd think Apple would match the banks if it did indeed make it better ... that is assuming they know this, which I would have thought they do.

It might be such a small improvement that they simply don't bother, but seeing as adding more anyway would be good to get it optimum.

Is confusing a bit.

It's nothing urgent anyway, just was interested in knowing and figured someone here might be a RAM guru and know all the real high level detail about these things

 

[mcobit]

What you refer to is dualchannel ramconfiguration.


It was a while back when tey introduced it and I am not sure if it still has any relevance these days.


As you said, the speedimprovements are very minor.


Why don't you just put them in there as you think is the best way, e.g. The two 4GB modules in slot 0 and the 8GB ones in slot 1 of each bank?


If it is an improvement, go with it. If you don't notice any difference, don't bother.

 

[Fzero]

Thanks, I shall do, probably/hopefully no real relevance these days anyway as you say, I just wasn't sure ... this is first I have even heard of such thing as dual channel ram config, I just assumed you could drop them in wherever was empty slots.

cheers for info

 

[Cas]

I use a Mac pro so...

Don't mix and match.

Insert them like either of these for fast Mem speed.

Slot 1. 8

Slot 2. 8

Slot 3. 4 

Slot 4. 4 

Keep the Mem sticks in pairs.

Basically it is a case of faster Mem speed if kept in prs, that's all.

 

[Binky]

Aren't banks 1 and 3 designed to work as a pair, as are 2 and 4

The image that was in the first post is broken - but I believe the slots were coloured alternately.

 

[Fzero]

Cheers Cas

Binky, don;t know why my MSPaint job has gone all deadlink in here but it still exists on the tinypic I posted it to;

http://i49.tinypic.com/24bkr6g.png

It is as you say, pairs are in odds & evens, 1&3, 2&4.

This photo I just found on a google search shows it better I guess

http://cdn.macworld.co.uk/cmsdata/reviews/3417250/iMac-27inch-24GB-RAM-Memory.jpg

That's how I will do it though

Slot 1. 8

Slot 2. 4

Slot 3. 8

Slot 4. 4

 

[Cas]

Cheers Cas

Binky, don;t know why my MSPaint job has gone all deadlink in here but it still exists on the tinypic I posted it to;

http://i49.tinypic.com/24bkr6g.png

It is as you say, pairs are in odds & evens, 1&3, 2&4.

This photo I just found on a google search shows it better I guess

http://cdn.macworld.co.uk/cmsdata/reviews/3417250/iMac-27inch-24GB-RAM-Memory.jpg

That's how I will do it though

Slot 1. 8

Slot 2. 4

Slot 3. 8

Slot 4. 4

I was explaining this for a  2009 Quad Core Mac Pro, different Mac Models have different Mem slot configs for adding memsticks.

Therefore can I suggest that you use this page and in the search put adding memory in a **********, the stars being your Mac model

http://support.apple.com/kb/index?page=search&product=&q=adding%20memory%20&src=support_site.kbase.search.searchresults