Advantages to matching RAM?

[alexf]

Hi Everyone,

Just a quick question for anyone kind enough to take a moment to answer:

I have a 24" 2.93GHz Core2 Duo iMac (last year's model) that shipped with 2 x 2GB (hence total 4GB) of RAM. I am starting to feel the crunch from more memory-intensive programs, and so the time has come to upgrade.

My question is: is there a clear performance advantage to installing matching RAM sizes, as opposed to 2 sticks of different sizes? I noticed that crucial.com currently offers an 8GB kit (2x4GB) for around $260. This is a bit beyond my budget, so I was thinking of instead just getting one 4GB through them for $130, and then mixing it with the Apple 2GB stick which is already in the computer.

Would I see a significant performance upgrade with the 6GB mismatched RAM vs. the 4GB matched?

Thanks in advance for any advice.

 

[telepati]

I have same idea. But cruial really expensive. I saw cheap RAM on OWC. OWC 8GB Ram 207$ 8GB Nuram RAM 167.99$. Nuram best price I've ever seen. I talk to OWC last night and only difference this two ram warranty options. I want to by 8GB ram on my machine but Im not sure this is really get big difference. Some peoople has a 8GB Ram. Please tell us what is the difference?

 

[Hellhammer]

Using matched pairs will fully enable dual-channeling but in theory, it should work with mismatched RAM. Besides, you will likely see bigger performance improvement due to the extra 2GB than what dual-channeling can ever offer because most apps don't need the extra memory bandwidth

 

[the.sheepdog]

I just got my mac back from service because of mismatched ram.

It worked fine for 3 years. then one day crashed and would not start. I was fearing a power supply or main board death.

The ram were both flawed. Crucial is what was in it and they are not good enough for a Mac.

The technician said use apple brand. Thats what I have now. 2 each 2 gig matched apple branded ram. when I do an apple and about this mac, it tells me 4GB 667 Mhz DDR2 SDram. I have a 2.16 GHz core 2 duo cpu

Before all it ever told me was 3GB SDram. I am convinced that matching ram from a good source is everything.

The tech said that Crucial only tests 2 points in the ram as thats all PC's check and thats most of their sales. Apple checks 7 points on the ram and your Mac does too. Thats why my Imac failed. one of those 7 areas eventually failed from being weak.

 

[TMRaven]

Dual channel memory bandwidth will be enabled when there's matching amounts of ram in both banks on intel mobos. If you're going to use one 2gig stick and one 4gig stick, then you probably might lose the dual channel, but as hellhammer said, often times it's more convenient to have more memory available than it is to have more memory bandwidth available, because not a lot of tasks take advantage of the higher memory bandwidth that dual channeling provides. Do note that clock rates or latency timings often have no impact on dual channeling or not, when it comes to intel mobos.

 

[alexf]

Thanks for the advice. However, Apple itself uses Crucial RAM as their "factory RAM" (or at least they used to) and that is why I usually try to buy from Crucial.

Over the last 7-8 years I have owned quite a few Macs (buying and selling) and often when I have opened them up, the "factory" RAM was either Crucial, Samsung, or Micron. I have never seen Apple factory RAM that is Apple labeled. Is this not the case any more?

I just got my mac back from service because of mismatched ram.

It worked fine for 3 years. then one day crashed and would not start. I was fearing a power supply or main board death.

The ram were both flawed. Crucial is what was in it and they are not good enough for a Mac.

The technician said use apple brand. Thats what I have now. 2 each 2 gig matched apple branded ram. when I do an apple and about this mac, it tells me 4GB 667 Mhz DDR2 SDram. I have a 2.16 GHz core 2 duo cpu

Before all it ever told me was 3GB SDram. I am convinced that matching ram from a good source is everything.

The tech said that Crucial only tests 2 points in the ram as thats all PC's check and thats most of their sales. Apple checks 7 points on the ram and your Mac does too. Thats why my Imac failed. one of those 7 areas eventually failed from being weak.

 

[DannyBres]

What a load of sales Bull$#!7, apple don't even make memory!

 

[Hellhammer]

I have never seen Apple factory RAM that is Apple labeled. Is this not the case any more?

Apple makes no hardware. Foxconn and other manufacturers manufacture Apple products so there is no "Apple factory". Apple uses various RAM brands, such as Samsung, Micron, Crucial and Hynix. Even the RAM Apple provides can be bad and so can be RAM from any manufacturer. Luckily, 3rd party sellers give lifetime warranty versus Apple's one-year warranty

Macs are made out of the same components that you can find from a Walmart PC. Some parts are custom such as the logic board but that doesn't change the story

 

[Fuchal]

Newegg has 2x4GB for $160 the last time I checked.

 

[aliensporebomb]

Ah

Newegg has 2x4GB for $160 the last time I checked.

That's a great deal. I got 2x4 GB for $199 last summer. I've been at 12 gig ever since and no problems at all.

 

[richpjr]

I just got my mac back from service because of mismatched ram.

It worked fine for 3 years. then one day crashed and would not start. I was fearing a power supply or main board death.

The ram were both flawed. Crucial is what was in it and they are not good enough for a Mac.

The technician said use apple brand. Thats what I have now. 2 each 2 gig matched apple branded ram. when I do an apple and about this mac, it tells me 4GB 667 Mhz DDR2 SDram. I have a 2.16 GHz core 2 duo cpu

Before all it ever told me was 3GB SDram. I am convinced that matching ram from a good source is everything.

The tech said that Crucial only tests 2 points in the ram as thats all PC's check and thats most of their sales. Apple checks 7 points on the ram and your Mac does too. Thats why my Imac failed. one of those 7 areas eventually failed from being weak.

Wow, what a snow job you got. Yes, memory can go bad but Apple does not make memory and Crucial is one of the most respected memory manufacturers out there.