1 or 2 sticks of RAM?

mw2fan

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May 4, 2011
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So I was at the PC store today, to pick up my homebuilt computer
(It was my first time building a pc, and it didn't boot, so I brought it there and it turned out I forgot to plug in the power button :/).
But the computer-guy told me that I should buy another stick of RAM,
because my processor doesn't function well with one stick of RAM.
Here's my specs:

CPU: Core i5 2500k
GPU: MSI r6870 HAWK
RAM: 1 stick of 4Gb Corsair valueselect 1333Mhz
MOBO: ASRock P67 Extreme4
PSU: Corsair 850Tx V2

I cheaped out on the RAM and bought 1 4Gb stick, for €25,
but would my processor really function better with an extra 4Gb stick,
or was the PC guy just trying to get me to buy more RAM?

Thanks in advance for all the replies,

-Mark
 

cmckay

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Matched sticks of RAM are required for dual channel support, so yes you would get a performance gain if you install two identical sticks. Now, that performance gain would be the same whether you installed 2 X 2GB sticks or 2 X 4GB sticks. Just a question of how much RAM you need/want/can afford.
 

mw2fan

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So it kinda works like SLI/CrossfireX right?
It splits the workload so 1 stick has to do less work..
I'll throw in an extra 4gb stick, they're not that expensive ATM.
How much of a performance gain would I see? 10-20%?

And even when a game/app doesn't take up all 8Gbs of RAM, would there still be an increase?

Thanks, Mark
 

cmckay

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Sorta. What dual channel does is give each memory module its own channel with the controller, effectively increasing memory throughput. Like a two lane highway vs a one lane. Performance increase depends on how large the chunks of data are that you are swapping in and out of memory. I have seen some benchmarks that only give a 5% increase in everyday use while performance in other programs such as video editing or gaming are significantly more.

As for amount of RAM, Windows 7 doesn't let much go to waste. Even if your apps aren't utilizing all your available memory, Windows 7 will cache frequently used programs so that they start quicker.

Your computer will run just fine with the 4gb stick, but if you game or do anything memory intensive like working with large spreadsheets or databases, you will want the performance increase. If the cost is negligible to you, I would recommend doing the upgrade as well. With RAM the more the merrier. I usually max out whatever the computer supports, as it enables me to get as much life out of the computer as I can, without worrying if a year down the road I have enough memory to run the latest version of whatever app.

Just remember in the future if you upgrade to do it in matching pairs or you won't be getting all you can out of your hardware.
 

aanthonyfranks

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Most computers these days support dual channel. In this configuration, speed is almost doubled by using two sticks. Please note that the rods are identical to the corresponding copies of the same make and model of the same size.

 

mw2fan

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Okay, thanks guys!
I'll be picking up another stick later this week, because I only paid 25 for one stick anyways :p.