What the cheapest way for me to get 64 bit Vista Ultimate on new PC?

Hi - I am about to buy a Dell Laptop (XPS M1530). I would like to try and install Vista Ultimate 64 bit, but I would like to be able to remove the 64 bit version and install the 32 bit version if I have too many headaches. What is the cheapest way for me to do this?

As I understand it, If I pay $150 dollars extra for my laptop to upgrade the OS to 32 bit Vista Ultimate (from the standard OS of 32 bit Vista Home Premium), I am not entitled automatically to the 64 bit version. So, I would have to spend another ~$190 for an OEM version of 64 bit Vista Ultimate.

Or, I guess, I could get the Dell Laptop with the 32 bit Vista Home Premium (no additional charge) and then buy a Retail version of Vista Ultimate, which would include the 32 bit and 64 bit disks. This would also cost about $350, but should give me the ABILITY to install EITHER the 64 bit or 32 bit versions.

There is also an "Upgrade" version of Vista Ultimate available for ~$250, which also contains the 32 bit and 64 bit disks, but I'm not sure it will even allow me to install the 64 bit OS if I don't already have a 64 bit OS installed.

Is there a cheaper way to get 64 bit Vista, with the luxury of dumping it for the 32 bit version if I can't get the 64 bit version to work? Does anyone have any experience with this?

Thanks, Michael

let us see what the Campustech price is

http://www.campustech.com/discount [...] sn160.html

$210 for Windows Vista Ultimate 64.

is that a good deal ?

i got Ultimate 32 for about $190. it has good
speech recognition capabilities.