(FZ series) SODIMM DDR2 800 MHz instead of 667MHz, does it work?

I know that the fz series are using SODIMM DDR2 200pin PC5300 667MHz but if I buy an exactly the same but with 800 MHz, is it going to work then? And does the fz use up all the 800 speed?

 

It will work, but only at 667 MHz. Save your $$.

 

Santa Rosa doesn't support DDR2 PC6400 yet, sorry =(

 

OK thanks everyboody.

But what about: If i'm buying PC5400 ?? Whats the different anyway between PC5400 and PC5300??

And one more question =),Is it correct that cas5 are faster/ better than cas4?

 

Yes it does. Check the auto-linked post from your post:

Not to mention all the other Santa Rosa specs and reviews that Google turns up.

And as further anecdotal evidence, my AR670 showed up on Friday, and I replaced the stock DDR2 667 modules with an OCZ 2GB DDR2 800 module (I'm waiting on the other backordered 2GB module to arrive). So even though I went from dual-channel mode to single-channel with this one module, Vista's memory performance index rose from 4.5 to 4.8. I imagine that running dual-channel when the other DDR2-800 stick arrives, it'll score a hair faster still. I didn't run any other memory benchmarks before replacing the RAM, so I don't have anything to compare other than that. Although if folks are too interested in knowing for sure, when I get the other 2GB stick I'd be willing to benchmark the pair against the stock 667Mhz modules.

 

No, lower CAS numbers are faster. So CAS4 is faster than CAS5. The number indicates CAS latency, or the number of clock cycles it takes for memory to be read.

 

Go to the Intel Site. They are the final say on what their own chipset supports. Santa Rosa does not support DDR2-800. It was supposed to but Intel was having issues with power consumption. It sort of defeats the purpose of having a faster FSB, but the FSB connects everything else with the processor so that is where the performance advantage is. But if you were to put in DDR2-800 memory it would not function at 800 but rather 667.

 

Perhaps you're right, but how does that explain my memory performance improving a few points after moving from dual-channel 2x512MB 667 to single-channel 1x2GB 800? I would have expected a memory benchmark to go down, not up, in that case.

However, in the interest of full-disclosure, since my last post in this thread, I have added the second 2GB 800Mhz module and my Vista memory score remained the same at 4.8, so apparently dual-channel doesn't have much effect on Vista's benchmark. Perhaps the latency on my OCZ was just better than the factory modules, but that's a bit unusual since latency usually increases with faster FSB modules. *shrug*