What model is your motherboard?
There are several numbers printed directly on Intel® Desktop Boards that are not indicative of board model. To identify the markings on your board that will help you identify your board model, refer to Find Support by Board AA Number.
I don't think a SATA driver for that would have been on the Intel site. That's a D955XUR, which isn't listed on the website at http://www.intel.com/support/chipsets/sb/cs-020684.htm, which means it's probably exclusive to Dell.
Unfortunately, that means "wait for Dell" - wish I had better news.
Finally, a friend found a driver somewhere on the web.
This plus the Raid drivers given by dell on a floppy disk, and I can boot a hard drive I recently buy.
Still have to find where the problem is (the raid isn't working and I would like to get the data back)but the PC is working now.
Thanks for the answers, it was very helpfull. It help my friend to find the driver.
It's more than probably a dell exclusive. And dell is not easy to join once the garanty is over(I am awfully busy with my work when the slow helpdesk is open).
Not very happy about this and not sure at all my next computer is going to be a dell (the very expensive configuration of the computer is not usefull at all once you want to add some hardware. I have to look at my new computer from dell if I have the same problem)