Can I Run 32-Bit Windows XP on a 64-Bit AMD/Intel Process

Yes, 32-bit is what most all users have. You won't see any tangible benefit from the 64-bit Windows unless you need more than 4GB of RAM.

Of course you can.
The reason why AMD extends the x86 instruction to 64-bit is to make it compatible with 32-bit legacy OS / programs.

Of course! Ask around... hardly anyone here runs a 64 bit OS on their 64 bit processor.

I am trying out 64-bit Vista, but find myself working on XP mostly --- software and driver support is still abysmal.
I knew that SOME people did use 64 bit versions of Windows (XP/Vista) ... but the vast, vast majority are just sticking with what works.

I am trying out 64-bit Vista, but find myself working on XP mostly --- software and driver support is still abysmal.
It isn't that bad.... well okay it is, but I'm finding work around's for them. Sometimes you can use either x64 drivers or just plain ol' 32 bit drivers.

I hope you're right.

Also hoping they lower the price of the OS. I'll stick with XP until they make it cheaper, regardless of whether or not I desperately need to upgrade to Vista.

Nowhere on the Vista site does it differentiate between the 32 bit and 64 bit editions... are you sure it's a 64 bit OS? In the upgrade matrix there is no upgrade path from the 64 bit XP... just sounds kinda backwards if you ask me.

that's no problem to continue  

Yes it will work... And also don't x64 windows it sucks trust me it really sucks!

Each version (except home basic I believe) will be available in a 32 and 64 bit version. Features between the two versions will be identical, it's just a 32 vs. 64 bit difference.

Thanks for your replies everyone.

Not to hijack the thread, but Linux 32-bit versions seem to have problems on 64-bit CPUs. I've tried to install 32-bit Linux OSes on my X2 3800+, and they either won't install (FC5) or I have stability problems (OpenSuSE 10.1).

Never tried 64-bit Windows on my box, it's gotten mixed emotions from users. The consensus is not to use it unless you need it (read: 4+ GB of RAM)

When AMD made thier 64 bit format for thier cpus they made the cpu also able to handle 32bit nativly as if it was a 32 bit processor when running 32bit applications. So by all means yes its going to run just as if it was a 32bit processor.

As for the linux thing just one more reason i stay away from it.

64 bit windows running 64 bit applications is way faster then 32bit but running 32 bit apps on a 64 bit piece of software as far as i know they didnt take much time in backwords compatability like amd did with thier cpu's

I dont use it because i dont really care.

My understanding is that the installer will check to see if your CPU is 64-bit capable. If it is, it will install the 64-bit version, if not then it installs the 32-bit.

Vista is geared for 64-bit, so most hardware support will be written for 64-bit. 32-bit will probably just have to get by with default MS drivers. There is already talk about devices such as HD/Blu-Ray DVD drives not going to be 32-bit compatible.

This also explains why XP-64 driver support sucks. Few users use x64, so hardware makers are concentating on Vista 64-bit drivers, rather than x64. I have x64 on my media server, and I can't get drivers for my network printer or scanner (both HP & both less than 1 year old). If I want to print anything from it, I have to use my MFC/fax machine shared on another computer.  

Yes.

With 64-bit cpu's you can run either version of windows. downside of running 64bit is that not everything else is compatible with it yet application wise.