1-2 year future use of DDR2 unbuffered PC2-4200...6400 240pin DIMM?

[QuixoticOne]

Given the current low memory prices of unbuffered non-ECC non-registered
DDR2 240pin DIMMs in speeds between 533MHz and 800Mhz, it's tempting to
stock up for future PC builds to occur over the next year or two.

I am more interested in memory QUANTITY than memory bandwidth performance
for some applications, though I'd appreciate the opportunity to use current
and next generation CPUs and motherboards with last year's commodity memory.

I'm wondering if chipsets on the known roadmap will likely continue to support
DDR2 in combination with the next year's generation of CPUs (FSB-1333 and up,
analogous situation for AMD)?

I've already ran into problems with the P35 chipset apparently not being able
to UNDERCLOCK the RAM relative to the CPU's FSB which seems to mean that
one couldn't use 266 MHz (=DDR2-533) memory with a 333 MHz FSB (=FSB1333)
CPU since the slowest memory clock is equal to the CPU FSB clock.

Ideally I'd like to think there would be known current or next generation
commodity chipsets that will support contemporary CPUs
(e.g. FSB1333) while also using 8GB or more (4x2GB) of
DDR2-unbuffered DIMMs at speeds of 266Mhz (DDR2-533=PC2-4200),
333MHz (DDR2-666=PC2-5200) to 400MHz (DDR2-800=PC2-6400).

Or has the time basically come that PC2-4200(266) memory is just not going to
be usable with any future CPUs beyond last year's FSB-266MHz CPU generation?

As there are already DDR2 DIMMs and chipset variants, will the next
generation (2008/2009) chipsets (even in the 'midrange' / 'consumer' markets)
be switching over to DDR3 exclusively so that one couldn't expect to be able
to use a surplus of DDR2-PC2-5300 or PC2-6400 memory without staying
with generation-old CPUs and motherboards?

 

[GundamF91]

From what I've read, it sounds like that DDR3 will take over after DDR2-1066/PC2-8500, and then escalate from that point on. So I would fully expect that DDR3 will start to come into its own around 2008, and probably reach critical mass by 2009. Since the notch is keyed differently, that means new motherboard too. And then probably new CPU slot

So basically I think just get enough for now, and then you'll have to upgrade anyway, rather than hoarding memory that'll be obsolete like the DDR of today.