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I've recently gone from a DDR2/LGA775 setup to a DDR3/LGA1155 setup. With DDR3, the timing numbers are quite a bit different than I am used to with DDR2.

My question is: Which is going to be more important for overall system performance, timings or command rate? I can get a command rate of 1T with timings of 9-9-9-24, or I can get timings of 7-7-7-20, but bump my command rate to 2T. I know with DDR1 and DDR2, having a 1T command rate was considered very good if you could get it without completely hosing your timings.

I have a 1600mhz rated RAM, but I am not running it at at that frequency. I am currently running it at the stock 1066mhz, with no real plans to change it, as I do a lot more random access on my computer than large sequential data sets. Unless I am misunderstanding DDR3 completely, I am going to get more out of decent timings and a good command rate than I am a high RAM frequency.

So, 1T command rate or tighter timings?

Some extra system info, in case it helps:

Core i5-2500k
MSI P67A-G43 (B3)
8GB (2x4GB) Corsair Dominator DDR3 
Windows 7 Pro 64-bit

My system is used mostly for gaming and development tasks.

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up vote 1 down vote accepted

This might help a little:

TomsHardware Memory timing

The graphs seem to indicate that higher ram frequency is more important than tighter timings.

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Hmm, if you read the "conclusions", that's not what they are saying at all. He in fact specifically says high memory frequency gains you less than tight timings in most situations. How are you reading the graphs that you got an opposite answer? Just curious – Matt Holmes May 18 '11 at 18:47
You're right, I somehow missed that. The Sandra and PCmark memory suite show increased memory bandwidth with higher clock speeds, but that doesn't seem to carry over into real world applications. – electricsauce May 18 '11 at 19:28
Well, in the end, you answered my question though, so I am going to go ahead and accept/upvote it. That link basically told me what I wanted to know. – Matt Holmes May 18 '11 at 20:18

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