I have an XPS M1330 with Windows Vista Home Premium 64-bit.  It is hands down the most unreliable item for sale on Dells website.  Almost every Windows update results in the machine being unable to boot up for various reasons.  The machine was brand new in February, and a Windows update in March caused a Blue Screen Stop error 0x000000F4.  Startup Repair, Safe Mode, and System Recovery tasks were unsuccessful.  Result was that I had to restore the machine to factory settings, losing all the information I had stored on it.  An important note is that Dell Tech Support provided absolutely no assistance in the matter...hiding behind the fact that I didn't not purchase a software warranty.  In June, a Windows Update cause my machine to not boot once again.  The software stated that "This copy of Windows is not Genuine".  Once again, no help from Dell, unsuccessful system recovery, and I had to restore the machine to factory settings.  Of course all my data was once again lost.  Now it is September, a Windows Update came through about a week ago that once again 0x000000F4.  The machine will not boot up, Startup Repair and System Recovery  tasks are unsuccessful.  This time Dell Tech Support is willing to help, but of course they are stating that my only option is to restore the machine to factory settings...once again losing all of my data.  I understand the need to back up a system.  But I also understand that if I purchase a $1500 laptop from Dell, I shouldn't have to restore it to factory settings THREE times in 7 months.  In addition, should it be a necessity to purchase an expensive external drive just because my expensive laptop?  Has anyone else experienced this level of unreliability with their Dell machine?  Has anyone had any luck getting Dell to stand behind the equipment they sell?  Are there any other options, such as reverting to XP, that can make this a reliable machine?  Thx.