DDR2 vs DDR3 using core 2 duo

BoBz89

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Hello,

I've seen a bunch of posts/reviews comparing DDR2 and DDR3 but almost all of them utilize the core 2 quad serires of processors to do their benchmarking. From what I've gathered, most of them conclude that DDR3 is a very very minor upgrade from DDR2.

So my question, will a core 2 duo (I'm looking at the E8500 in particular combined with probably an x48 MB) benefit in any way shape or form from upgrading to DDR3?

Thanks!
 

Zenthar

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Not really, it only benefits the i7 and I'm pretty sure it has more to do with the on-die memory controller than the DDR3 itself.

While on the subject: what was the whole point of DDR3 anyway? They lowered the voltage (hurray!!! :-/), doubled the speed, but doubled the latency as well ... It would be like doubling the speed of a CPU, but also doubling the number of processing required for every instruction ... oh wait, that was the P4 ... Still, I find this ridiculous.
 

zodiacfml

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DDR3 uses a smaller manufacturing process compared to DDR2 and minor improvements to allow the memory go higher frequencies and easily reach huge memory sizes. it is still better.
reason for small performance improvement is memory bandwidth had catch up with the speed of CPUs compared to old DDR1 and past memory technologies using single channel.
 

freelancer87

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So now the argument is not the money or the latencies, cause those are almost the same as ddr2 now, but just that the core 2 duo with the x48 chipset cant significantly benefit from the extra speed (1600 mhz and higher) from the ddr3 memory.

Do I understand this correctly?

and

Is this because of a probable bad on-die memory controller or lack of bandwith from the c2d's or c2d's cant just handle those memory speeds or am I all wrong about this one:)?
 

You basically have it. As for the reason, it's because the memory controller is in the chipset, and the front side bus on the CPU does not allow enough bandwidth for the CPU to gain the full benefit from faster memory. It's bottlenecked at the FSB. This is fixed in i7 because it has no FSB, relying instead on a direct memory controller on the CPU.
 

freelancer87

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Im also doing some research on overclocking(I have never overclocked in my life), but what if you use the ddr 3 1600 mhz with a memory divider 1:2 or some other ratio on a core 2 duo like the e8500 with a higher fsb.

Will this help a bit with the FSB bottleneck or will I still not benefit from the ddr3 with other memory dividers?


Im already really thankfull for your answers btw, thank you.
 
You still really won't benefit, unless you go high enough that DDR2 can't keep up at a 1:1 ratio (so to outrun the capabilities of DDR2-1066, you'd need to push your FSB to 533 quad pumped, or 2133 MHz).
 

freelancer87

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what if you use FSB 400/450/500 quad pumped with ddr3 1600/1800/2000 mhz with higher multipliers. Will this still not help, or is this not even possible?
 

freelancer87

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You mean ddr3 has to run at half the speed for 1:1. Ok, I misunderstood quad pumped then, I thought the memory was quad pumped, but its the FSB that you have to do times 4 and the memory is dual pumped then.
So FSB/4 and memoryspeed/2. thx dude, you were very helpfull.


 
Correct :)

You can absolutely run the memory at the same (effective) speed as the FSB, and it will work (it's considered a 2:1 ratio on most boards), it just won't give you any noticeable speed benefits.
 

freelancer87

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Ohke thank you, im gonne buy 1066 ddr2 and use it with a wolfdale standard clock at 3.16 Ghz and overclock it of course:D. I want to reach at least a stable 4.0 Ghz without raising the processor temp too much:D.

L8er