Should using SSE2 work on Xen now ? There is an email thread from several years ago that said that it didn't. I'm running an i386 NetBSD 5 DOMU on top of an amd64 NetBSD-current DOM0. On the DOMU I get: machdep.fpu_present = 1 machdep.osfxsr = 0 machdep.sse = 0 machdep.sse2 = 0 machdep.cpu_brand = Intel(R) Atom(TM) CPU 230 @ 1.60GHz Robert Swindells