Old Fixed-Sync Monitors under Linux?

Hautis asks: "I read somewhere that it should be possible to use huge, old fixed-sync monitors with any (*vga) video card under Linux, once you tell XFree86 the exact sync ranges or whatever values it needs. I happen to have a couple of old VAXen, that is, VAXstations, lying around in my family's cellar. 19 inch mono and RGB tubes, fixed sync. What kind of cables would I need (I can solder well enough)? Would I be able to use text modes also, would a frame buffer beneeded for this? What about (S)VGAlib? Can I have two graphics adapters, one conn't to my crappy old 15-inch and one to the huge ancient particle accelerator? Or should I switch between the displays when I want to use X? Will I get a cancer for staying up nights surrounded by 80's display technology?"