Memory quality or quantity

mpvm

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Sep 29, 2009
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Hi there...

I am about to assemble my own comouter and
I was wondering what memory i was going to buy :)
The motherboard supports DDR3 and triple channel...
But should i go for the quality (high mHz, triple-channel ect.) or the quantity (GB)?

For example:

Kingston KHX1333C7D3K2/4G
4 GB (8 GB, i'll buy two of them), dual-channel, 1333 mhz, DDR3, latency timings: 7-7-7
approx. $ 260 ($ 130 for 1)

OR

Kingston KHX2000C9D3T1K3/6GX
6 GB (6 GB, i'll buy 1 of them), triple-channel, 2000 mhz, DDR3, latency timings: 9-9-9
approx. $ 240
 

Mongox

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Aug 19, 2009
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Triple channel will always outperform dual-channel - given equal amts of RAM which isn't possible of course.

More RAM will always outperform less RAM. Given the same # of channels.

Lower latency RAM will always outperform higher at the same MHz speed.

You cannot ask which is better - 8GBs of dual-channel RAM or 6GBs of triple-channel. It's like asking whether a 69 Roadrunner is better than a 73 Jaguar XKE. Two different vehicles designed for different things - but both the fastest cars made in their years.

See, it's basically a trick question - since there is no answer. See My Cousin Vinny for more explanation.

Like MaD above, I'd go for the 1600 with nice CL numbers.
 

MaDMagik

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Oct 12, 2008
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If you really need to choose between the two than I suggest the triple channel kit. But again I advise you to read the article I linked, or even go straight to test results and see how minor the improvements are in most cases. Unless you plan to work on your pc all day compressing stuff with winrar - than yes, faster memory can save you some time then. Otherwise something like that kit i linked will be just as good and the $100-something saved can be pumped into better gfx card or cpu, something that will have VISIBLE impact on overall performance. Believe it, even though you pay twice the amount you dont get twice the performance, very, VERY far from that(more like 5-10% at best). But do as you wish
 
Triple-channel memory can read 3 items in the same time that dual-channel memory can read 2, so on the face of it you'd think that you're getting a 50% performance boost. But because of the large caches in modern CPUs, RAM isn't actually accessed very frequently. At a 95% cache hit rate, only 5% of the instructions which access memory (and not all of them do) will actually have to go out to RAM to get the data. If you speed up those 5% of instructions by 50%, you're only getting a 2-3% performance improvement overall. That's why there's not all that much point in spending a lot of time worrying about memory performance.