Is a quad-channel kit something special or basically just two dual-channel kits?

[TheDarkKnight]

I am thinking of buying a 16GB(4x4GB)quad-channel kit of DDR3 memory right now since it seems to be just a little better deal than buying an 8GB(2x4GB) dual-channel kit of memory.

If I did purchase the quad-channel kit could those 4 chips ever be split up and used as 2 8GB dual-channel kits or are dual-channel and quad-channel memory chips functionally different in some way?

 

[mmaestro]

It's just a box/blister with 4 identical sticks of memory, so no problems splitting it between 2 systems.

 

[TheDarkKnight]

It's just a box/blister with 4 identical sticks of memory, so no problems splitting it between 2 systems.

I found this comment on the Valve Steam forums regarding a similar topic:
"AMD specifically states that their next generation of memory controllers (those present in the Zambezi processors) will be able to directly address four distinct channels of memory."

Here's the thread if anyone is interested:
http://forums.steampowered.com/forums/showthread.php?t=1942138

So, while it may be true now, that a quad-channel memory kit is two dual-channel memory kits that are being sold together this may not be true in the future. This topic will inevitably confuse many people for years to come.

 

[greenhawk]

I found this comment on the Valve Steam forums regarding a similar topic:
"AMD specifically states that their next generation of memory controllers (those present in the Zambezi processors) will be able to directly address four distinct channels of memory."

someone is smoking something

from wiki

http://en.wikipedia.org/wiki/List_of_future_AMD_microprocessors#.22Zambezi.22_.2832_nm.2C_8-core.29

Advanced Dual-Channel DDR3 Memory Sub-System

AMD does have a quad channel CPU comming, it is the Interlagos and will be like Intel's s2011/SB-E chip. Aimed at servers and extream performance users. The average user will be unlikly to afford (or willing) to buy them.

This topic will inevitably confuse many people for years to come.

It has been confusing people since the first "dual channel" ram was released. Then again when tripple channel was released for the original i7/

 

[TemjinGold]

I am thinking of buying a 16GB(4x4GB)quad-channel kit of DDR3 memory right now since it seems to be just a little better deal than buying an 8GB(2x4GB) dual-channel kit of memory.

If I did purchase the quad-channel kit could those 4 chips ever be split up and used as 2 8GB dual-channel kits or are dual-channel and quad-channel memory chips functionally different in some way?

I believe the only difference is that the four sticks were specifically tested to work together whereas two separate dual packs may or may not work well together. They can definitely work as 2 duals.

 

[Soulkeeper]

TemjinGold is correct

I think what constitutes a "quad-channel kit" depends on the marketer/manufacturer
ie: I'd expect them to put all 4 modules in a motherboard and verify that they work at rated clock/latency/voltage together, but who knows what one manufacturer may/not do.

 

[greenhawk]

I believe the only difference is that the four sticks were specifically tested to work together whereas two separate dual packs may or may not work well together. They can definitely work as 2 duals.

Given that any ram, by definition of meeting a given spec, will work find with any other stick rated at the same spec. No extra testing needed as that is why specs / specifications exist.

Now if it was a high end ram tested to run at speeds inexcess of the standard spec then I can agree, but then the same process of testing binning occures for the faster speeds resulting in batching of ram without testing the ram together as a set.

So once again, if buying ram of the same timings/specs, it does not mater if they came in the same box as each indivual needs to meet the advertised spec level. Otherwise you can return it can get another one as the product is faulty / does not work as advertised.

With all that taken into account, expecting the ram to be tested to work together is just marketing talk to convince you it is a better way to buy your ram. If anything, a pack should be cheaper than the individual units on the grounds of less handeling alone, but like that has ever been a reason for manufactures to pass on lower costs.

One 4x4GB pack I was looking at last month was cheaper than 2 dual packs which was cheaper than buying the sticks individually. Unfortunitly for some brands, that is not true, they still ask more per set than for individual ram of the same timings and claim "testing" as the reason. It is only marketing of the same goods as I see it. Each to their own though in the end.