Running memory faster on Conroe than FSB

I have been looking at some conroe MBs lately and all of them recommend DDR2 800. My question is why? Isn't the FSB 200? Shouldn't it only need DDR2 400 then? Do they want you to run memory at a higher memory-to-fsb ratio now? I'm confused since I've been out of the comp building game since when anything but a 1:1 ratio was unacceptable.

For instance I have a P4 630 Dell comp right now that came with DDR2 533. When I look at CPUz the memory is running at a 3:4 fsb:memory ratio so while the FSB is 200mhz, the memory is running at 266mhz. Is this optimal now to have the memory running faster than the FSB on Intel platforms? How is it for the new AM2 AMD platforms? Any help sorting this out would be much obliged (didn't see anything about the newer stuff in the FAQ). Thanks.

fsb is 266mhz

The conroe is very different than all the past cpu's and a good cpu to that.

Also a very easy cpu to overclock.Also because its FSB is so high that after a certain overclock you start to see very minimal gain , the other thing is that the bandwidth it needs to grow and you will see whist overclocking the core 2 that the ram cant keep up with it.

Take the am2 , it has a lot of ram bandwidth but the cpu falls behind and for the conroe its the other way round.

The CPU is so powerful that the ram falls behind and this being the reason why you start to see little gain after a certain overclock.

Usually about 1ghz on every cpu. But this said you canj only keep up with tight latencies but this becomes to expensive. A very efficient cpu and 1ghz overclock is more than enough cos after that you will need more ram bandwidth and this grows very slowly with conroe.

This is the reason why i think they kept the fsb at what they have left it at.

So if you are overclocking then i would advise you tight ddr800 if you are going to overclock and would advise you not to go over what your ram is rated at but keep tight latencies which will give you a optimum overclock.

Ok I am still pretty confused, so what memory should people get if they don't plan to overclock? Should the memory be run at a 1:1 ratio with the FSB or should it be run faster?

Still something which can give you a tight latency if you can afford it , thats just added goodness.You tend to loose performance in the early rated ddr2 modules cos the latencies are loose and then start seeing gains in higher rated modules.(with tight latencies)

Eclipse has said the ddr2 latncy devide it by two and it will roughly be the same performance as what you will see in a ddr1 modules .
I would try and get cas3 533mhz , this way you will still see good performance on the modules.

I have seen loose timing modules in ddr2 at 533 and it becomes a bottleneck for your system.

CL3 at 533 or CL4 at 667mhz is the way forward. Also at the mo both of these are hot sellers which will mean good price.Aint that right Eclipse , wheres he gone again?

yup

some ddr2-533 would be my advice if you're set on no overclocking, as it's 1:1 with the FSB and can still be found in relatively low latency forms

He is back and he has bought his wisdom along with him, great man.