Don't shout, please. I know about the DX10 for XP "hack", but it's not supported by Microsoft so forgive me for being sceptical.
I can't find a comparative benchmark right now, but I'd be willing to bet the 9400 is slower than the 8600.
if i was being rude but i change the card third time i will get overclocked 9500gt GDDR3 .I want to play crysis at 1024x800 (or even at 800x 600 resolution if you say ) and I want the settings at low with 30FPS will it be able to play.
But the problem is the CPU is change to old and dirty P4 3.4GHz .
so final specs....
pentium 4 3.4GHz
9500gt 1GB GDDR3
dx compatible sound card
windows xp 32bit
Crysis is a bad game to use as a benchmark for building a computer. It runs poorly on machines that can happily play most every other game out there. You have to think a bit broader than just upgrading you computer to run Crysis.
If you are a serious gamer, I would recommend you save a bit longer and go for an entirely new build. P4 + 9500GT won't get you far in the long term.