Windows 7: understanding CPU-Z

Layback Bear · 02 Mar 2012

If CPU-Z shows DRAM Frequency at 600 and you have duel channel that would mean your ram is working at 1200.
If one has DDR 3 on a 3 channel motherboard DRAM Frequency 600 is that ram still working at 1200 or 1800?
N/B frequency at 2400

soho1 · 02 Mar 2012

I would have thought each channel is a maximum and that there is nothing additive. On the other hand, you might get a better answer from your average barista, as I have no idea. But I'm curious now and will follow your thread.

GeneO · 02 Mar 2012

The times two is from double data rate (DDR), not the number of channels. So 1200.

Layback Bear · 02 Mar 2012

DDR-2 = 2 DATA RATES/600 X 2 =1200 Ram speed
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DDR-3 = 3 DATA RATES/ /600 X 3 = 1800 Ram speed ????
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The reason I ask is my DRAM frequency is 850 and I have DDR-3. I'm thinking that it is still X 2 @ 1700 because I don't see how it could be at 850 X 3 = 2550 Ram speed.

GeneO · 02 Mar 2012

No DDRx = Double Data Rate, type x. The x is not a multiplier for speed. DDR3 is not triple channel. I am running Dual Channel DDR3 memory for instance. The x is an interface specification. DDR3 is an interface specification for Double Data Rate type 3.

So for all DDRx memory, CPU-Z will show 1/2 the memory frequency.

Edit: I forgot the details: DDR does 2 transfers each clock cycle. So the 600 is the actual clock rate.

GeneO · 02 Mar 2012

So let me add a little more.

For 1200 MHz DDR (800 Mhz clock) you will see a bandwidth of up to
1200 x (64 bits / 8 biits per byte) x 2 = 19,200 MB/s for dual channel memory and
1200 x (64/8) x 3 = 28,800 MB/s for triple channel

So you aren't being cheated

Layback Bear · 02 Mar 2012

I don't think I'm being cheated, that is not why I'm asking the question.
The (X) is not a multiplier, that helps me understand.
Sorry for the confusion on my part.

GeneO · 02 Mar 2012

Common misunderstanding. I was just joking about feeling cheated

Windows 7: understanding CPU-Z

understanding CPU-Z problems?