  Modern PC workstations often provide more CPU power than required for most
control applications. On the other hand, the screen space is always in short
supply. One possible solution is to use more PCs, but in fact we need only more
screens, not more keyboards, mice etc. PC architecture allows using more than
one videocard, and X Window protocol is also aware that there can be more than
one screen. But until release of XFree86 version 4 there was no freely
available server capable of driving multiple ``heads''. We have been using
multiheaded workstations under XFree86 in the VEPP-5 control room since early
2000 (currently 4 4-headed PCs plus several dual-headed). The ``Xinerama'' mode
(one-large-screen) is better suited for accelerator control system than
``several separate screens''. When moving to this configuration we've
encountered a number of, mainly human-related, problems, some of which required
modifications to X server Additionaly, the ``style'' of performing control has
slightly changed.
