I've read the Anandtech articles on RAM and MCH timing with great interest, and intend to make use of this info in a new build. But of course it won't be exactly what you tested and I'm left with a few questions.
I need 4GB minimum RAM, and prefer it to be 2x2GB as I might later expand. I will use DDR3 since I want high speed and 4GB is affordable for me now. I know DDR2 is much cheaper but have decided against it. For similar reasons I will get a QX9650 CPU - it keeps options open and is affordable (on ebay).
I will be using an ASUS X48 motherboard; either the P5E3 Premium or Rampage Extreme if that is ever produced.
Getting to the questions:
I'd like to achieve 450MHz FSB, but I want to keep tRD down to 6 max. I can still upclock my unlocked CPU from a lower FSB eg 400MHz. I know that adding banks of RAM increases tRFC. And I know the electrical characteristics of DDR3 (with on-board terms) will differ from DDR2. So...
? With DDR3, will using 2x2GB be better or worse for RAM timings than 4x1GB? Is it worse than 2x1GB?
? With 2x2GB will even DDR3-1800 timings (eg 7-7-7-20) degrade to the point where I can't achieve 450MHz FSB (with low tRD)? Is the prognosis any different for 4x1GB?
? To ask the above in another way: Will staying at 400MHz FSB allow me to run a tRD of 5 to 6 even with 4GB?
Thanks for any insights!
Arbie
I need 4GB minimum RAM, and prefer it to be 2x2GB as I might later expand. I will use DDR3 since I want high speed and 4GB is affordable for me now. I know DDR2 is much cheaper but have decided against it. For similar reasons I will get a QX9650 CPU - it keeps options open and is affordable (on ebay).
I will be using an ASUS X48 motherboard; either the P5E3 Premium or Rampage Extreme if that is ever produced.
Getting to the questions:
I'd like to achieve 450MHz FSB, but I want to keep tRD down to 6 max. I can still upclock my unlocked CPU from a lower FSB eg 400MHz. I know that adding banks of RAM increases tRFC. And I know the electrical characteristics of DDR3 (with on-board terms) will differ from DDR2. So...
? With DDR3, will using 2x2GB be better or worse for RAM timings than 4x1GB? Is it worse than 2x1GB?
? With 2x2GB will even DDR3-1800 timings (eg 7-7-7-20) degrade to the point where I can't achieve 450MHz FSB (with low tRD)? Is the prognosis any different for 4x1GB?
? To ask the above in another way: Will staying at 400MHz FSB allow me to run a tRD of 5 to 6 even with 4GB?
Thanks for any insights!
Arbie