My guess is you're running Vista? Then again, we really shouldn't have to guess at what could be contributing to the problem. As mentioned you made a rather vague post. How about including your system spec, OS, and symptoms of your problem as well as driver version?
If you read through the customer reviews for the biggest selling 9800X2 on Newegg (EVGA), you will find a mixed bag of those whom say the drivers work OK and those whom say they don't. Those having no problems are generally using the latest beta drivers. Those having problems are commonly running Vista. Some are even saying it works fine in quad SLI.
It's not surprising however that there would be some driver issues with this card as the 7950GX2 was plagued with them. I have been very skeptical ever since Nvidia unveiled plans to use almost the exact same architechture in this version of GX2 except of course for a different GPU.
Some have surmised that the quality and brand of MB you mount it on could be part of issue, perhaps minimizing compatibility problems. I have heard some say that ASUS MBs are less likely to exhibit such problems. Others have said that ASUS video cards are rock solid too.
Whatever the case, it's almost a given that Nvidia is partly to blame. I find it odd that many are now praising them for releasing drivers so often when in fact it shows they are in constant need of fixing.
I have come to the resolve that the best way to buy an Nvidia card is to stick with one of their high end single GPU cards like the upcoming 9900GTX. However, I am also considering ATI's 4870 X2. Their dual GPU cards seem to run cooler, use the full 1GB VRAM vs half, are mounted on a single board vs two which traps heat, can Xfire with ANY game even on Intel chipsets, and are priced much better.
http://www.newegg.com/Product/ProductReview.aspx?Item=N82E16814130338&SortField= 0&SummaryType=0&Pagesize=100&SelectedRating=-1&PurchaseMark=&VideoOnlyMark=False&Page=