Settings - Cas2 400MHZ 6-3-3 or 7-2-2

[DDogg]

My Nforce2 400 MoBo will run Kingston Hyper-X Dual channel at a 200 clock with settings at Cas-2 7-2-2 and memtest shows it is faster than Cas-2 6-3-3 (1538 mb/s vs. 1460 mb/s) so that sounds good to me. However I keep seeing stuff about ram "sync" and "async" which I don't really understand and it has me royally confused. I would appreciate some education from somebody that has a good handle on the subject.

I guess the question would be whether fastest is necessarily the best setting and what is meant by ram "sync" or "async"?

[Solo]

Hi
Cas-2 7-2-2 will be faster than Cas-2 6-3-3 that is a fact.
Which HyperX you got? I have the DDR434.
Running memory "sync" means that your memory and your FSB are running at the same speed. "Async" means that they are runnig at different speeds. For example when I installed my new AMD Barton 333 FSB CPU on my nForce board with DDR400 memory I had to set my FSB to 166 (333)but by default my memory was running at 200 mhz (async). Now for best possible performance you want to be running your memory and CPU at same speed. So in your BIOS you are going to want to set it to 1:1 or 100% or whatever under advanced options or user defined or what ever.

If your HyperX is rated at CL2 and it is DDR400 then you'll get CL2 at that FSB but once you start going over your memory timings will get worse and performance will get worse.

So if you have DDR400 memory and a 400 FSB Barton even better as you can run both at 200(400). It starts to get more exciting when you start overclocking. You can set your 166(333) FSB CPU to run at 200(400) with memory @ 1:1 for better performance. Or if you have DDR434 you can go up to 434 FSB with memory running sync and the performance in games in particular gets even better.

I hope this helps and that I didn't get too carried away but the whole overclocking bug has bitten me big time and I could still start with memory and Intel systems and how that differs from AMD but I thinks I answered your basic question already.

[DDogg]

In my mind I think I was trying to make it was more complicated than it really was as I have always run my ram in sync I now realize. For some reason I had it in my head that the other ram settings somehow caused some type of "hand-off" problem and could slow things up so I thought 6-3-3 might actually be faster in communicating with the CPU or bus than 7-2-2. I thought that is what they were talking about as sync or async.

Thanks for clearing it up for me. So my hyper_X 3500 is in sync. Rocking machine with a cost under 400 bucks that runs CCE at 3X realtime on some 16:9 encodes. Can't complain at all :)

/ADD: OK, I was getting two separate things confused. "Any tRAS setting lower tRCD + CAS + 2 cycles will allow the memory controller to close the page “in your face!” over and again and that will cause a performance hit because of a truncated transfer that needs to be repeated." http://www.mushkin.com/mushkin/pop-up/latencies.htm

So, with my Cas2 7-2-2 I guess this is saying I could use Cas2 6-2-2, but I don't think I will even worry about it.
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