I've read that AM3 CPU's will be backward compatible with socket AM2, however the AM3 will carry a DDR2 and DDR3 memory controller allowing the use of either (not both). And i was wondering, if the memory controller is on the chip and not the northbridge, could you theoretically use DDR3 in an AM2 board with an AM3 cpu? Or must it be designed for such things? That'd be pretty awesome if it were possible. I'd have to automatically assume the answer is no, since there would almost be no point in releasing an AM3 socket if you could take advantage of AM3 cpu's with an AM2 board. However it still makes me wonder since the northbridge doesnt dictate to the mobo what memory is allowed considering the controller is on the CPU. I'm all excited for K8L. So many exciting things will happen. 65nm, 4 cores, coprocessors, low power consumption. AMD is really stepping it up here with K8L. Go read the wikipedia article for K8L. At the very least it has articles at the bottom to back it up related to what's defined for it. That still doesn't answer my question though!
This caught my eye: (This article was found by alpine_sc)
Not only this, but the big shock is RD600 was designed for the ground up to support not only DDR-2 but also upcoming DDR-3 memory. In fact, ATI has already fully tested DDR-3 memory on RD600 and it is working fine, months ahead of before it is due to be released for public consumption. ATI are ready for DDR-3 memory whenever it enters the market, which is likely after Q2 2007, according to our sources. Since DDR-3 memory uses a different slot to DDR-2, you won’t be able to use new DDR-3 memory on current RD600 motherboards you buy this year or early next year. As well as the new memory slot, our friends in the bunker also told us that a new PCB design is required but it only requires a very small change to the internal circuitry – nothing too complex.
That should answer your question, despite the fact that it's meant for Socket T.
One more thing - Don't put 100% faith into AMD when it comes to AM3 compatability. They're going to try to make it happen, but AM3 is still a little ways off, and problems requiring changes in the chipset or voltage regulators could always spring up.
yes it did thanks. now that i think about it, even if it were compatible, i'd end up having to get a new mobo and ram anyway. AM3 in an AM2 board with DDR2 ram to upgrade to AM3 board and DDR3 memory. But i wonder how badly DDR3 latency will affect AM3 considering how much DDR2 cripples AM2 now. We'll have to see i guess what kind of improvements they'll make on everything for K8L.