While Technically XP ( 32 bit) can run on 64 MB and a lot of older machines were sold with 128 MB installed these amounts do not make it with modern programs.  
    Running 512 Mb  allows for getting the email , writing letters etc.  It really doesn't do well with Graphics intensive programs , movies, running a number of programs all open  etc.
  Running Between 1GB and 2GB is the optimal amount for XP when running the modern programs and a number of them at once.
    Running over 2 GB does not add anything to the system except, maybe make you feel good.


Please NOTE THAT IN ADDING MEMORY TO YOUR MACHINE TO BE SURE THAT THE MACHINE WILL ACCEPT WHAT YOU ARE TRYING TO ADD . Older machines and Dell computers may well be restricted in what they can address.  XP machines may only be able to hold 1GB

If you are looking to buy a machine  Be sure the above is adhered to. Many are still out there that will not do the Job, Especially with Windows 7 around the corner and you wanting to upgrade.  If your are buying think about 64 bit architecture in your machine.    This applies to the NET PCs and some of the smaller Laptops.  Most Desktops over $500 can be expected to be OK.  However ask the sales staff. If they don't know Call us with the  Make and Model # of the machine your are interested in.

###---###---###---###---###---###---###---###---###---###---###---
Complete Computer repairs, upgrading and optimizing for all systems.  Fast improvement to your sluggish and shaky system.  Make the old machine hum again.
Gary Orthuber
Cal-Pac Computing
300 Montgomery Ave. Oxnard CA. 93036 ( El Rio)
(805) 988-9540
http://www.calpactech.com
E Mail:  nccorthu@...