These are binaries only. The linux version is 64-bit only. http://www.bitcoin.org/download/bitcoin-0.3.13.1-specialbuild-win32.zip http://www.bitcoin.org/download/bitcoin-0.3.13.1-specialbuild-linux64.tar.gz
The linux 64-bit version includes a change to the cpuid 4-way 128-bit SSE2 autodetect for AMD in 64-bit mode, if you'd like to test that and see if that's better.