I personally would take the replacement machine offer vs. allowing Dell to continue to send parts after parts - in a heartbeat. I may be wrong, but your situation seem to me like a protracted lemon deal.
As far as the Vista vs. XP choice, unless they plan on sending you a blatantly outdated machine--I doubt they'll do that--to replace your current lemon, I suggest to let them pre-install Vista on it for you. The fact is, XP is history ... but still relevant to some than others, especially folks with older peripheral equipments. My guess is, you'll be better prepared for the future with a Vista loaded replacement than an XP option.
For what it's worth, Dell is still offering XP on new machines. The Dell rep that's helping you may not be empowered or authorized to pitch XP to customers - for obvious reasons. But you can get XP on the machine if you are adamant about having it - though, you may have to pay anywhere from $50 - $100, depending on what version of Vista the machine is supposed to come with ... see below.
"Is there any way to get Windows XP after June 18th?
Customers may continue to get Windows XP Professional by purchasing a PC with Windows Vista Business BONUS or Windows Vista Ultimate BONUS, which allows Dell to exercise "Windows Vista downgrade rights" on your behalf by preinstalling Windows XP Professional and providing the installation disc for either Windows Vista Business or Windows Vista Ultimate so that you may transition to Vista when you are ready.
What are Windows Vista “Downgrade Rights”?
Windows Vista Business and Windows Vista Ultimate have what Microsoft calls “Downgrade Rights.” Downgrade Rights means that anyone with a Windows Vista Business or Windows Vista Ultimate operating system can downgrade to Windows XP Professional provided they have the media for Windows XP Professional. Customers may use one operating system at any single point in time (cannot run both operating systems simultaneously unless an additional license is purchased).
For customers who decide to exercise Downgrade Rights on their own, however, please note that Dell will only support the pre-installed operating system. Windows Vista Home Basic and Windows Vista Home Premium do not have this option, as they are not capable of downgrading to Windows XP.
When you are configuring your system online or through the help of one of our sales experts, you will have the opportunity to select which operating system you would like on your PC. When selecting your operating system, you will see an option called “Genuine Windows® Vista Business BONUS” and “Genuine Windows® Vista Ultimate BONUS.” With these options, you may purchase the licensed rights to Windows Vista but have Dell pre install Windows XP Professional. You will also receive a backup media disc for Windows XP Professional as well as the media for Windows Vista so you can upgrade when you’re ready. Furthermore, with these options Dell will provide technical support for the pre-installed Windows XP Professional image and your licensed version of Windows Vista.
Can I downgrade on my own?
Yes, you can as long as you have your own Windows XP Professional media (i.e. from a prior purchase). However, Dell’s standard policy is to provide technical support on the operating system that comes pre-installed on your PC. Dell does not encourage you to change your operating system on your own as this can be a complicated process.
If I choose to have Dell downgrade for me, does that mean I can only get technical support on Windows XP Professional since that is what will be pre-installed?
No, with this option Dell will provide technical support on both Windows XP Professional and Windows Vista Business or Windows Vista Ultimate (depending on which version you choose).
I don’t need Windows XP Professional, but I still want Windows XP Home Edition. Is there any way for me to get this from Dell?
No, Windows XP Home Edition and Windows XP MCE both End-of-Life (EOL) on June 30, 2008 and do not have the capability to transition to Windows Vista (i.e. these licenses do not include Downgrade Rights provisions). Microsoft created that capability only with Windows XP Professional, Windows Vista Business and Windows Vista Ultimate. Windows Vista Home Basic and Windows Vista Home Premium are unable to downgrade to Windows XP.
What do I do when I’m ready to upgrade my computer to Windows Vista?
You will use the Windows Vista DVD provided to you to install Windows Vista on your computer. If you upgrade and then realize you’re not quite ready for Windows Vista yet, you also have the freedom to go back to Windows XP Professional using the Windows XP Professional CD provided with the downgrade service."
http://www.dell.com/dellhasanswers
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