I built a new desktop last year with a 64 Bit processor but did not want to drop the $ on a new OS at the time. I continue to use the 32 Bit Version of XP. I have 4 GB of RAM but can only use about 3 of it due to the video card RAM and XP's 4 GB limit. I do not want to go to Win 7, I'd like to upgrade to the 64-Bit version of XP. Are there compatibility issues with going to Win XP 64 Bit for older drivers, programs, etc?
I have a laptop with Win 7 Home and have had some trouble getting older programs and devices to run on it - hence the reason to avoid it on the desktop.
Yes, there are some driver issues with XP 64 bit. The resources weren't put into 64 bit XP support, because Vista 64 bit was about to be released. The driver support is lacking, software isn't always compatible, and the performance increase from the added RAM will be negligible.
Your laptop probably doesn't meet the virtualization requirements, but your desktop might. If your desktop hardware meets the requirements, you can use virtual xp mode, to get around the compatibility issues. http://news.cnet.com/8301-13860_3-10229125-56.html