Question Dual Channel higher latency or Single Channel lower latency ?

Mawla

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May 21, 2021
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Which RAM will be faster - dual channel, higher latency or single channel, lower latency?
Example: DDR5 5600MHz - 2x8GB CL46 or 1x16GB CL36

If it depends on the application, please give examples.
 
Always? I see this double bandwidth thing everywhere and I understand the principle. But how does it translate to real world performance?

Most side-by-side test results favour dual channel by up to ~10% in some cases; and by less than 1% in some. In a few cases, the single channel actually does slightly better.

Anyway, in all the tests I've seen, the RAM latencies are the same or unspecified. That's why I asked.
 
Always? I see this double bandwidth thing everywhere and I understand the principle. But how does it translate to real world performance?

Most side-by-side test results favour dual channel by up to ~10% in some cases; and by less than 1% in some. In a few cases, the single channel actually does slightly better.

Anyway, in all the tests I've seen, the RAM latencies are the same or unspecified. That's why I asked.
I question why not both, dual channel with low latency RAM?
Lower frequency usually has lower latency than those of higher frequency. Your example shows very low quality ram.

At 5600MHz Cl36 is very low quality ram and Cl 46 would be dismal junk !!! In real work both would be dogs.
DDR5 at 5600MHz should have at most Cl30 or 28 to be effective. In any case Cl is not as important as other latencies and values that have to be in tune with it.

All things being equal, frequency and Cl, in dual channel theoretical Bandwidth and with it performance is 10-30% better than same RAM in single channel no matter which capacity. Those differences can be seen mostly while benchmarking but in real life it also depends on OS and software depending how they use RAM, some prefer low latency and some higher frequency but if you have lousy RAM it would be bad for everything equally.