Yes there are DX10 Only effects in Crysis, which obviously requires a DX10 3D card and vista. But they're incidental ones that can only been seen by nitpicking at screenshots. What makes Crysis look a million times better in vista than it does in XP is the very high detail setting. In XP you're limited to getting High. However that's purely an artificial lock down by sinister forces unknown, and very high is indeed available to all XP types with a spot of easy tweaking. 

WARNING PLEASE READ THIS TUTORIAL THROUGH A COUPLE OF TIMES BEFORE ATTEMPTING TO DO THIS. 

Where To Start 

The first thing you need to do is head over to your Crysis install folder. You're most likely to find this by navigating to C:\Program Files\Electronic Arts\Crytek\Crysis\. Once you've located it bring up \Game\Config\CvarGroups, and save a copy of all the files within it. This will be your backup if you end make a silly boo-boo. Next, open up the first .cfg file in Notepad (or which ever text editor you prefer using). 

Getting High 

The First paragraph in the file the Windows Vista-exclusive Very High Settings; the last paragraph is high. So it's just a matter of tricking Crysis into thinking Very High is merely high. Copy the contents of the first paragraph over the contents of the last paragraph. Repeat this for each of the cfg files, and then load up the game. Nothing will appear different in the settings menu, but if you select High, you'll find that, in game, its actually very high. Take that Man. 

Slowing Down 

There's one downside: the game in very high is likely to run about as fast as a heroin-addled hedgehog unless your toting SLI 8800's or a mega-overclock. At the time of writing this is true in either XP or vista. However inside the Bin32 folder in your Crysis install directory are two .bat files that benchmark your card and CPU, so you'll be able to see how much performance impact the hack has had. 

Adapted from PC Format Magazine - Issue 209 January 2008 

Hope this gives an extra graphics boost to an already beautiful game 

Welshy