RAM - 4 4GB sticks or 2 8GB Sticks?

[TheOnlyCorwin]

I am buying a new computer and wondering if I should buy my 16GB of RAM with 4 4GB sticks or 2 8GB Sticks?

Also, Geil brand is about $30 cheaper than Corsair.
Is RAM just RAM? Or should I shell out the money for Corsair?

Thanks!

 

[Woomack]

Everything from Corsair except Dominator series is just standard RAM and I see no reason why other ( at least these more popular ) brands could be worse.
I would pick 2 stick kit unless you are planning to use X79 platform ... so 2x 8GB.
Crucial 1866 9-9-9 1.5V is nice but not so cheap. Something 1600 from G.Skill can get for half price.

 

[hokiealumnus]

+1 to everything Woomack said. (It's nice to go to a thread and not have to really say anything other than affirm a very knowledgeable answer!)

 

[TheOnlyCorwin]

Thanks guys!
Also, if I am using a Z68 platform and use 4 sticks of 4GB instead of 2 of 8GB, is there a difference in the amount I will get out of them?
Basically, what is the reason that 2X8 is better than 4X4?

(I just know nothing about RAM!)

 

[Woomack]

For Z68 based boards max is 32GB so you can make it only with 8GB sticks in 4 slots ( if you will ever need it ).
2 sticks are stressing IMC less than 4. Simply it's usually easier to set high clocks with 2 sticks than 4+. Also 2 sticks can usually work with tighter timings or at least command rate 1T instead of 2T.
Not all memory kits will make declared speed in 4 stick configuration or you will have to set higher IMC voltage to make them run stable ( that's not a rule but it happens ).

 

[cbo329]

Everything from Corsair except Dominator series is just standard RAM and I see no reason why other ( at least these more popular ) brands could be worse.
I would pick 2 stick kit unless you are planning to use X79 platform ... so 2x 8GB.
Crucial 1866 9-9-9 1.5V is nice but not so cheap. Something 1600 from G.Skill can get for half price.

Hey Woomack, I was curious as to the comment about the X79 platform. I've recently started getting parts for a new 3930k/Sabertooth X79 machine. I was planning on using Coursair Vengeance 1866 sticks 16GB (2x8gb).. would (4x4gb) be better, and if so, why?

Any feedback would be greatly appreciated!

 

[Woomack]

Depends what are you planning to do on this rig. For most things there is no difference if you get 2x8GB or 4x4GB but since your new platform can support 4 channel memory then I would get 4x4GB.

 

[xchaoticx]

hi, im new to the forums. I found this thread and thought it would be a good place to start finding an answer to my issue. I have an Asus q550 and it maxes out at 16 gb of ram at 1600, I have 8 right now, 2x4gb of manufacturers ram. I want to upgrade to 16gb and am wondering if its better to get just 2x4gb of something, or get 2x8gb of ram and replace whats existing with something possibly better. And again wondering if filling just 2 slots is better that all 4 or not? thanx for any help and if theres any info I can give to help let me know

 

[xchaoticx]

anyone wanna jump in??help

 

[bob4933]

Shouldn't matter too much. For starters, unless you're doing some ridiculous video editing, 8gb is PLENTY for almost anything.

That said, its always best to use the smallest amounts of slots available. Dual channel mode is best, so 2x8 would be the way to go, all things else considered equal. If its significantly cheaper to get 4x4, I would go that route, else 2x8 just makes more sense.

 

[xchaoticx]

thanx man, really appreciated, and good brands you could recommend?

 

[bob4933]

Any of the "usual suspects" is fine. Corsair, crucial, gskill, kingston, whatever honestly.

Just remember, for "normal" aspects, 8gb is fine, and the speed isn't that important either. I.e. BF4 on ultra, 8gb is plenty.

 

[Tyerker]

thanx man, really appreciated, and good brands you could recommend?

If your motherboard tops out at 16GB, then you are probably better off getting a better set of 2x8GB. If you get another set of 2x4GB, the speed and timings will sync to the lowest common denominator, meaning it will likely run slower than what is listed.

As far as brands, G Skill is the only RAM I have ever had die on me. I am a big fan of Patrioit, but I have had good luck with Crucial and Corsair, as well.

 

[bob4933]

I have seen good results and reviews from gskill, but I am a crucial man myself as well.

 

[magellan]

Depends what are you planning to do on this rig. For most things there is no difference if you get 2x8GB or 4x4GB but since your new platform can support 4 channel memory then I would get 4x4GB.

IBM has a whitepaper article where they did extended testing w/their LGA2011 based servers and found 4 channels give measurably better performance in all the apps they tested.

They also found that memory bank interleaving also had a measurable performance increase as well, but not as much as having 4 channel interleaving.

The biggest influence they found was memory speed.

 

[EarthDog]

Depends what are you planning to do on this rig. For most things there is no difference if you get 2x8GB or 4x4GB but since your new platform can support 4 channel memory then I would get 4x4GB.

IBM has a whitepaper article where they did extended testing w/their LGA2011 based servers and found 4 channels give measurably better performance in all the apps they tested.

They also found that memory bank interleaving also had a measurable performance increase as well, but not as much as having 4 channel interleaving.

The biggest influence they found was memory speed.

It appears what they tested is bandiwidth needy. That is not the case in most home PC environments however. Remember that analogy I mentioned a while back... the 'which flows faster, a 1GPM spicket with a garden hose on it, or a 1GPM spicket with a firehose on it? That is a decent analogy for ram. If the application you use does not saturate the available bandwidth of dual channel, it won't get any faster with quad channel. Or in other words, which is faster, 20GB/s or 20GB/s? LOL! It doesn't matter until you are saturating the bandiwidth.

 

[magellan]

It appears what they tested is bandiwidth needy. That is not the case in most home PC environments however. Remember that analogy I mentioned a while back... the 'which flows faster, a 1GPM spicket with a garden hose on it, or a 1GPM spicket with a firehose on it? That is a decent analogy for ram. If the application you use does not saturate the available bandwidth of dual channel, it won't get any faster with quad channel. Or in other words, which is faster, 20GB/s or 20GB/s? LOL! It doesn't matter until you are saturating the bandiwidth.

Memory bank interleaving primarily reduces latency. I believe there is also channel bank interleaving that does something similar. I think in both cases the more banks/channels there are the more a positive effect is seen.

 

[Crapxxas119]

Memory bank interleaving primarily reduces latency. I believe there is also channel bank interleaving that does something similar. I think in both cases the more banks/channels there are the more a positive effect is seen.

I think the point that Earthdog made was that the difference is minimal. It may make something load in a blink of the eye but to the average user it would be no different.

Also that IBM article was on a 2011 platform which uses quad channel memory which makes use of the 4 channels. On an 1155 platform there is only support for dual channel memory (if i remember correctly) so it treats the 2 4GB sticks in each channel as one 8GB stick. This means that there is no benefit in using a 4x4GB set of RAM. Plus i have heard that running 2 sticks in one channel stresses the IMC a little more than one stick per channel. Plus getting a 2x8GB configuration will leave you room for upgrading later on.

 

[JeremyCT]

Ideally, you use the same number of sticks as your platform has memory controllers.

Simple. Straightforward.

If you don't how many memory controllers your platform has (single, dual, triple, quad) I suppose you could ask, but a simple internet search will yield the answer without admitting to everyone here that you didn't know.

 

[magellan]

I think the point that Earthdog made was that the difference is minimal. It may make something load in a blink of the eye but to the average user it would be no different.

Also that IBM article was on a 2011 platform which uses quad channel memory which makes use of the 4 channels. On an 1155 platform there is only support for dual channel memory (if i remember correctly) so it treats the 2 4GB sticks in each channel as one 8GB stick. This means that there is no benefit in using a 4x4GB set of RAM. Plus i have heard that running 2 sticks in one channel stresses the IMC a little more than one stick per channel. Plus getting a 2x8GB configuration will leave you room for upgrading later on.

I read over and old LGA1366 Westmere whitepaper by Fujitsu and they had
some SPECint_rate_base2006 benchmarks that indicated going from 2-way channel interleaving to 1-way channel interleaving resulted in a 19% loss in performance. Going from 3-way channel interleaving to 2-way channel interleaving only lost 5%. What's interesting is that the losses are higher for the higher performance Westmere's.

The stream benchmarks indicate an incredible loss in bandwidth. 30% going
from 3-way channel interleaving to 2-way, and 31% from 2-way to 1-way.

Their testing of even bank interleaved setups showed minimal differences of 1% to 2% over odd bank interleaved setups.

The title of the article is:
WHITE PAPER
FUJITSU PRIMERGY SERVERS
MEMORY PERFORMANCE OF XEON 5600 (WESTMERE-EP) BASED SYSTEMS

But I guess benchmarks don't really have much to do with reality.