I've been looking for the new core 2 duos. Just one thing which isn't really clear. What kind of mem should I put there?

I mean that they sell them with everything from 533Mhz DDR2 to 1066MHz. Usually they are tested with 667MHz or 800. The bus seems to be 1066MHz so if the logic goes like in my old system (P4 Northwood) the mem speed is half of the bus (800->400Mhz). So if the 533 would be enough then why the heck use so much faster mem if it is not overclocked? Just waste of money. No intensions to overclock it, just doesn't want memory being the bottleneck.

And is the logic same in AMD cpus? If I would for some whimsy reason buy one (1000 bus->??? mem).

Ideas?
TIA

The current FSB clock speed on the Core 2 Duo is 266MHz. Since it is a quad data rate bus, it is effectively 1066MHz. Using a 1:1 memory ratio, all you would need is DDR2-533, which is 266MHz RAM at an effective rate of 533MHz. Likewise, DDR2-800 is 400MHz RAM at an effective rate of 800MHz, and uses a 3:2 memory ratio when used in conjunction with the standard 266MHz FSB.

I personally bought two 1GB sticks of DDR2-800, and I'm running them with the 1:1 memory ratio, so they're only running at DDR2-533 speed. There is minimal difference in peformance as far as i can tell, but it is nice to know that you won't have to buy MORE RAM if you decide to use your current RAM in a new system with a higher FSB. Also, there is a very small difference in price between DDR2-533 and DDR2-800. At the moment, I don't think DDR2-1066 is worth it.

Ok, many thanks.

Kind of what I was expecting or understood from reading magazines.

Welcome.