This is beta 3 for version 3.7.1 of POV-Ray.
Note: To be able to improve performance of the 64-bit binaries, we have decided to limit support for Windows XP and Windows Server 2003 to the 32-bit binaries from now on. Since the installer was not updated in time to reflect this, users of x64 editions of such legacy systems may need to manual edit the links and file type assignments to point to pvengine32-sse2.exe instead of pvengine64.