ok first, dx10 dosnt requier unified shaders, read the specs yourself, its reccomended but no current card really uses it, the
8800 isnt unified, its a shitload of pipes and shader units, they wont give you the info on real specs but hell, what do you expect.
and dx10 class fetures should be 98% compatable with x1k cards due to how programable they are, older cards.....well no, but the code could be recompiled to run better on x800 range cards with more fetures then normal dx9 mode gives.
by the time vista is mature, the next version of windows will be out and ready for use, i wouldnt pay for vista period, its just not worth it.
dx10 could be made by ms to support 2k and up, it would just be a matter of ms accepting that people dont want vista and want dx10 for xp, hell i know ppl who would PAY for that addon!!!!!
but ms wants to push vista on EVERYBODY, i hear ms is PISSED that dell is offering xp again, cant blame them its "old news" and they got this new thing called vista they want to try and convence everybody is "better in every way on all hardware" when really its just bloated betaware shit, i have installed and tested vista on 6 systems, its NEVER been faster then 2000 or 2003, duno about xp, i gave up on xp long ago, to many problems for me(hotfixes/critical hotfixes/critical security updates that break shit.....piss me off)
i would like to see MS do something smart and put out a new vista like os thats more like 2003 server, vs xp, cut down, clean, fast, stable, none of the problems or bloat that the desktop versions force you to deal with......
and this isnt pure dx10 software emulation, its not using software to emulate missing fetures, its converting the code to run using current videocards.
i hope they can manage this, allow people with high end ati hardware at least play dx10 games on their curent hardware with their current windows