Hi, I have used Compaq Visual Fortran 6.5 for years. Recently bought a new PC with Intel Core2 Quad Q6600 processor and Windows Vista 64 bit Home Premium OS (yes, likely a mistake on the OS). I wish to use Code I wrote in the past and take advantage of 64bit processor, memory, etc. I have been unable to find a free (or inexpensive) 64 bit fortran compiler for Windows. Perhaps I have misunderstood what info I have found on the web. I considered shelling out the $2k for Intel's latest version, which is supposed to be compatible with Compaq Visual Fortran, but it appears to require Windows' SDK, which I read to not be supported by Windows Vista Home (go figure). Before I break down and buy another hard drive and install Linux (which I wish to avoid the effort and the maintenance on another OS), does anyone have knowledge to help? If not with the Windows, with the selection of Linux OS versions (there are so many) and a compatible Fortran compiler for Linux and Compaq Visual Fortran code (I have all the source code still, obviously). I appreciate it.