New iMac, Upgraded Ram, But Ram Running @ 1333mhz

[Jazwire]

Just got my new 2012 iMac set up, I ordered it with 16 gb (2x8) , and then purchased a Corsair Vengeance Kit from Amazon (the one several people have linked in here) it is 1600mhz ram I'm looking right at the box as I type.

The model number of the ram confirms it is 1600mhz, CMSX16GX3M2A1600C10

But when I go to "About this Mac" it does show correctly 32GB, but it's running at 1333mhz not 1600mhz.

And if I go to Hardware/Memory it shows all 4 sticks running at 1333mhz.


Any ideas???

[bflowers]

Maybe the RAM was spec'd wrong. Had it's setting clocked at the lower speed. I had RAM that was deactivated by an Apple Firmware update. Sent it back to the manufacturer (DataMem) and they flashed the settings and sent it back. Many happy years of service after that.

[WilliamG]

Originally Posted by Jazwire

Just got my new 2012 iMac set up, I ordered it with 16 gb (2x8) , and then purchased a Corsair Vengeance Kit from Amazon (the one several people have linked in here) it is 1600mhz ram I'm looking right at the box as I type.

The model number of the ram confirms it is 1600mhz, CMSX16GX3M2A1600C10

But when I go to "About this Mac" it does show correctly 32GB, but it's running at 1333mhz not 1600mhz.

And if I go to Hardware/Memory it shows all 4 sticks running at 1333mhz.


Any ideas???

Have you tried with just the one pair? I believe they work in pairs, missing every other slot, so 1 and 3 are one pair, and 2 and 4 are the other (if I believe what I read in some other thread - I guess I don't know how they came from Apple?). I'm curious as to what happens when you use just the Apple RAM, and then just the Corsair RAM. Keep us posted, please!

[bflowers]

Originally Posted by WilliamG

Have you tried with just the one pair? I believe they work in pairs, missing every other slot, so 1 and 3 are one pair, and 2 and 4 are the other. I'm curious as to what happens when you use just the Apple RAM, and then just the Corsair RAM. Keep us posted, please!

I checked with Apple on 11/30, and they confirmed my suspicion, and the commonly agreed upon position of several of us discussing it in another thread. Apple will have filled the first two slots with the base RAM, which are the first pair. The second pair is empty. You don't want to fill every other, leaving empty spaces in the middle.

That said, I agree, he should take them and try each one in turn. He'd need to do them as matched pairs in the first two slots. Combinations of AB, AC, AD, BC, BD, CD will help him sort it out if there are one or two bad DIMMS.

[WilliamG]

Originally Posted by bflowers

I checked with Apple on 11/30, and they confirmed my suspicion, and the commonly agreed upon position of several of us discussing it in another thread. Apple will have filled the first two slots with the base RAM, which are the first pair. The second pair is empty. You don't want to fill every other, leaving empty spaces in the middle.

That said, I agree, he should take them and try each one in turn. He'd need to do them as matched pairs in the first two slots. Combinations of AB, AC, AD, BC, BD, CD will help him sort it out if there are one or two bad DIMMS.

Good to know. Either way, I'd love to know what's going on here since I'm going to be using this very RAM in my soon-to-be-delivered iMac.

[Arman]

Same here. I would be a little upset having paid a bit of a premium for this ram.

[bflowers]

He also might want to put the original RAM back in, either separately or during testing the others, and see what the speed reads on the 2x4GB.

[bobright]

Originally Posted by WilliamG

Good to know. Either way, I'd love to know what's going on here since I'm going to be using this very RAM in my soon-to-be-delivered iMac.

Hey William your everywhere mate

I have this exact RAM purchased from amazon OP it is this one right? http://www.amazon.com/gp/product/B0076W9Q5A/ref=oh_details_o00_s00_i00

So it won't work correctly, are you guys returning them? I'm clueless on this as far as hardware just wanted to pop them in I'm glad to have read this. I haven't got them yet will be here on Monday so I'll just not even open them.

[Jazwire]

Originally Posted by bobright

Hey William your everywhere mate

I have this exact RAM purchased from amazon OP it is this one right? http://www.amazon.com/gp/product/B00...ls_o00_s00_i00

So it won't work correctly, are you guys returning them? I'm clueless on this as far as hardware just wanted to pop them in I'm glad to have read this. I haven't got them yet will be here on Monday so I'll just not even open them.

That is the ram I bought.
So yes it works, but doesn't play well with stock ram.(if you plan on keeping the stock ram and adding this, it appears it will indeed underclock the ram.)

Im not getting errors or anything, it just running the ram slower than it should be running.

I am undecided on returning it , or just buying another 16gb as this ram is better than the stock, better timings etc.)
I think I'm better off trying to get the same ram as Apple used (Hynix) if I can though.

[studiojackson]

Originally Posted by WilliamG

Good to know. Either way, I'd love to know what's going on here since I'm going to be using this very RAM in my soon-to-be-delivered iMac.

Ny 27 arrived today. When I popped the back (after reading this thread) I expected to see either the top or bottom slots filled. They were staggered.
I just added the memory to the open slots.
Went from 16 to 32 G All humming at 1600 MHz
Good luck.
OWC memory used

[WilliamG]

Originally Posted by studiojackson

Ny 27 arrived today. When I popped the back (after reading this thread) I expected to see either the top or bottom slots filled. They were staggered.
I just added the memory to the open slots.
Went from 16 to 32 G All humming at 1600 MHz
Good luck.
OWC memory used

Interesting. So you have the same memory amount as the original poster, and added the same amount to the Apple RAM. Difference is that you used OWC.

I still have to ask.... if you're going to pop off the panel and replace the memory anyway, why not buy it with 8GB of RAM, and replace all 4 sticks for 32GB? Cheaper, right?

[bflowers]

Did you try the ordering that WilliamG suggested? Just in case I (and logic) am wrong? I did check with Apple, but you never know if the rep I spoke with knew what he was talking about. Logically, it would make sense for the installed pair to be properly installed for maximum utilization, but stranger things have happened.

Go ahead and see what happens when you go 8/4/8/4 and let us know.

Originally Posted by WilliamG

Have you tried with just the one pair? I believe they work in pairs, missing every other slot, so 1 and 3 are one pair, and 2 and 4 are the other (if I believe what I read in some other thread - I guess I don't know how they came from Apple?). I'm curious as to what happens when you use just the Apple RAM, and then just the Corsair RAM. Keep us posted, please!

[Jazwire]

Originally Posted by bflowers

Did you try the ordering that WilliamG suggested? Just in case I (and logic) am wrong? I did check with Apple, but you never know if the rep I spoke with knew what he was talking about. Logically, it would make sense for the installed pair to be properly installed for maximum utilization, but stranger things have happened.

Go ahead and see what happens when you go 8/4/8/4 and let us know.

I already tried putting the ram in different slots.

By default the stock ram in slots 1&3 , so I put the Corsair in 2&4.
Then I tried stock ram in slot 1&2 Corsair in 3&4, and that made no difference.

----------

Originally Posted by edry.hilario

Cool, thanks for sharing the info. Are you going to order another 16gb pack? If you so please keep us posted just to make sure they do run well with the whole 32gb

Actually I think I am going to order another set of the Corsair from Amazon , since I actually could use the stock ram I have now on another machine I have.

[edry.hilario]

Originally Posted by Jazwire

I already tried putting the ram in different slots.

By default the stock ram in slots 1&3 , so I put the Corsair in 2&4.
Then I tried stock ram in slot 1&2 Corsair in 3&4, and that made no difference.

----------



Actually I think I am going to order another set of the Corsair from Amazon , since I actually could use the stock ram I have now on another machine I have.

Ok thanks please let us know how that goes since I almost bought that ram today I just want to make sure I want to make moneys worth I highly appreciate this info

[Jazwire]

Originally Posted by edry.hilario

Ok thanks please let us know how that goes since I almost bought that ram today I just want to make sure I want to make moneys worth I highly appreciate this info

Yep just placed the order, should be here Monday. I'll update this thread with my findings. (Which I am sure will be it works fine if you use all Corsair.)

[ViperDesign]

Just order 32GB of the same memory and it seems it will work fine. Sell the apple ram

[WilliamG]

Good to know it's just the mixing of brands causing the issue. Shame that happens, though. And it seems the stock RAM really does come in slots 1 and 3. Also good to know!

And yes, I am everywhere, bahaha!

[tonyep]

I'm running 4x 8GB corsair vengeance on mine and it's running at 1600mhz.

[Jazwire]

Originally Posted by tonyep

I'm running 4x 8GB corsair vengeance on mine and it's running at 1600mhz.

Thanks for confirming. Just be running a tad slower till Monday.
(Honestly probably not even notice it.)

[zarf2007]

can anyone confirm if adding crucial memory causes it to underclock? I am planning to add 2 x 8gb crucial to the the stock 2 x 4gb from apple to make 24gb total for my incoming 2012 iMac.

[bobright]

Originally Posted by zarf2007

can anyone confirm if adding crucial memory causes it to underclock? I am planning to add 2 x 8gb crucial to the the stock 2 x 4gb from apple to make 24gb total for my incoming 2012 iMac.

I want to know this as well, better yet a brand via amazon that works as I got gift cards there.

[Overg]

Interesting findings and of the most interesting thread.
Now I wonder what to do? Another cheap apple trick?!
So actually what you say is you need to buy all over again the memory cards, and ditch the apple one.
Btw what brand is apple? Are they manufacturing their own memory?

[bobright]

Has anybody tested Crucial RAM with the stock Apple RAM do they not underclock together?

I'd appreciate some input as I'm looking to return the Corsair for Crucial if I can through amazon. It is the perfect sweet spot for me 24GB of RAM including Apple's stock.

[Icaras]

Would also like to know about Crucial + Apple RAM.

Thumbs up for making this thread.

[bugbear99]

Is both stock and cosair run at 1.5v for 1600mhz?