Yes.
My AMD 64 processor works just fine with XP.
"AMD Turion 64 mobile technology is designed to be the most advanced family
of 32- and 64-bit Windows® - compatible processors available for mobile PCs,
allowing the freedom to work, relax and play virtually anywhere, anytime". http://www.amd.com/us-en/Processors/ProductInformation/0,,30_118_12651,00.html