Can my pc support a 64 bit operating system such as xp 64

I am currently using a Dell Dimension E520 celeron d 3.06 GHz and have to much ram for win xp 32 to read. maximum being 3 gigs i have 5.5. My question is can i run a 64 bit os such as windows xp 64 bit without running into internal problems. I eagerly await a response before i fork over the cash for a new version of windows.

5.5 gig? What size sticks and how do you have them installed?
What are you doing that you need so much RAM? 4 gig is plenty enough for all but the most demanding users running XP.
I see the post above, but seriously, a Ramdisk? This is an ancient technique from days gone by when RAM was expensive.
I would not buy XP64, not a lot of support for it, and it is outdated.
If you want a new 64 bit OS, go straight for Windows 7.
Go here download and run this, it will tell you of any compatibilty problems.
http://www.microsoft.com/downloads [...] laylang=en
If you can run a 64 bit OS, you can download the pre-release version of Windows 7, or just wait for the official release in a few months.

Personally, I would remove all but 4 gig, preferably 2x2 gig, and you will be just fine running XP. There is no reason to want to more, since the OS can't use it all, and you most likely won't actually need more anyway, especially with a Celeron system.
More memory would be the least of your bottleneck worries, the very, very least.

I have 2x2 gig sticks a one gig and the 512 that came with the system. I used that windows upgrade advisor and my system is able to run it so get will windows 7 in a few months and may possibly try the RAMdisk until that but i have only skimmed over the link for that. I will have to read more into it after work. Once more I appreciate the fast responses and info. if you have any more suggestions I'm all ears.