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I get the feeling DDR is newer and faster. I have a KM2M motherboard that will take 2 sticks of either DDR or SDR; cannot use both at same time. I currently have the 2 slots of SDR filled with 256 and I'm planning on upping that to at least 2 sticks of 512. Any input here greatly appreciated.
Thanks, Giddyup

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Last Post by GiddyupGilbert
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"Theoretically DDR-SDRAM provides double the bandwidth of normal SDRAM. At 100 MHz memory clock it's able to supply a data bandwidth of 1600 MB/s, at 133 MHz it goes up to 2100 MB/s. That is why 'Team DDR' decided to call the specs of those two DDR-memory types 'PC1600' and 'PC2100'. However, I have to disappoint you, if you should think that DDR-SDRAM is simply twice as fast as SDRAM at single data rate. The basic reason is rather simple. While DDR-SDRAM is indeed able to provide double the peak bandwidth of normal SDRAM, it has still the same (CL2 DDR-SDRAM) or even a slightly worse latency (CL 2.5 DDR-SDRAM) than its older sibling. The result is that in worst-case situations DDR-SDRAM can be as slow or even slightly slower than normal SDRAM. At the same time DDR-SDRAM can easily outperform single data rate SDRAM under ideal conditions. In average, systems with DDR-SDRAM are most certainly faster than systems with normal SDRAM, but the gain depends on the application and can hardly ever reach more than 20%."

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Dynamite input, just what I was looking for
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"Theoretically DDR-SDRAM provides double the bandwidth of normal SDRAM. At 100 MHz memory clock it's able to supply a data bandwidth of 1600 MB/s, at 133 MHz it goes up to 2100 MB/s. That is why 'Team DDR' decided to call the specs of those two DDR-memory types 'PC1600' and 'PC2100'. However, I have to disappoint you, if you should think that DDR-SDRAM is simply twice as fast as SDRAM at single data rate. The basic reason is rather simple. While DDR-SDRAM is indeed able to provide double the peak bandwidth of normal SDRAM, it has still the same (CL2 DDR-SDRAM) or even a slightly worse latency (CL 2.5 DDR-SDRAM) than its older sibling. The result is that in worst-case situations DDR-SDRAM can be as slow or even slightly slower than normal SDRAM. At the same time DDR-SDRAM can easily outperform single data rate SDRAM under ideal conditions. In average, systems with DDR-SDRAM are most certainly faster than systems with normal SDRAM, but the gain depends on the application and can hardly ever reach more than 20%."

Great info; does give me a better picture of the dif. I will go with the DDR even if only a 20% gain. I will be going from 512SD to 2 gig DDR. I figure just the volume along will have my sys operating more efficiently. Thanks for your input, a definite input of good info.
Giddyup

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