Specific Memory Question: low latency+$$$ vs faster-$$$

sidhe

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Nov 25, 2002
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I am building a new quad core rig using a 680i mobo and this is the memory I had planned to buy...

Corsair 2GB DDR2 800 (PC2 6400) 4-4-4-12.

However, I just found the following on newegg for $15 less

Crucial 2GB DDR2 1000 (PC2 8000) 5-5-5-15

So since they are virtually the same cost my question is: do I go for the faster PC2 8000 with higher latency or the PC2 6400 with the lower latency? Note that I will not be doing much in the way of overclocking if that matters. Primary purpose of this rig is gaming.

Thanks in advance,
 

NotAPimecone

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Nov 18, 2006
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I bet you wouldn't notice any difference. The higher latency would hurt performance a little, but the higher speed would help. And you might even be able to underclock the 1000MHz CL5 to 800MHz CL4 anyway (I know I can run my 4-4-4-12 DDR2-800 at 5-5-5-15 well over 900MHz).

Anyway, I bet 1000MHz RAM at 5-5-5-15 is faster (probably not very noticable in real-life use) than 800MHz RAM at 4-4-4-12. But you'd need, like, a 15:8 ratio (or a 3.75 multiplier) to get 1000MHz RAM at 266MHz FSB. I guess it would (maybe) still run 5-5-5-15 at 2:1 (1066MHz), so that's probably what you'd end up using. Unless you OC to 333 FSB and run 3:2.

I'm not an expert, though. I'm basing most of what I'm saying on the results in this article.
 

The-Darkening

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Hello!
I Don't know if my logic is correct but I think it is, so I share it with you.

If you buy the DDR2 1000, even with latency 5 it should be faster than the DDR2 800 low lat. The thing is, you should check the latency table for the DDR2 1000 and see what latencies it uses "downgraded" to DDR2 800.

I'm almost sure that it runs 4.4.4.12 in DDR2 800, and being cheaper to boot, would be the best option.

Now, can someone confirm this?
 

nobly

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Same performance IF you can run them at max speeds.
Getting it to 500Mhz might be asking too much though.

But you might be able to pull off 4-4-4 w/ the 5-5-5 RAM if its clocked lower. I'd look more into if the 5-5-5 RAM can run 4-4-4 if you underclock it to 800Mhz. If you can, easy answer.