Well, if you can get the cooling system from whatever vendor you plan to purchas the 6800 Ultra from then it should not be too difficult. I imagine we will see some post around here before mid summer with people who have achieved such a feat. But at what cost? Are you willing to void your warenty AND pay $400+ (guessing here but 9800 was $399) more dollars IF you can get ahold of an Ultra?
Here is what the cooling system looks like:http://www6.tomshardware.com/mobile/...ll_xps-04.html
Also Dell did promise "And graphisc Upgrade to XPS2 if one becomes available"
So eventually you will probably want to replace your 9300s Ultra with that card too.
Just curious, if it means that much to you, i would pony up the dollars now and get the XPS2 to be safe. Then again I like to play it safe, i am not a big gambler.