I'm about to get a new system. Currently in favour of Athlon 64, and I expect to get something like a Radeon 9800 or nVidea 6600GT. Looking at prices, it seems to be cheaper for the PCI-Express versions of the cards - although compatible motherboards are a little more (not sure if any are available for another week or so), making the total about the same. Is there any reason not to go for PCI-E? Have there been any real tests yet to see if it's quicker?