I've only got one protected-mode game that is listed as supported (UFO / X-Com, http://dosbox.sourceforge.net/comp_list.php?showID=1334&letter=U), however it dies, even if you follow their directions for switching the soundcard IRQ and/or disabling sound for the game. I tried recompiling dosbox with lower-optimization CFLAGS, but it didn't make any difference. Reproducible: Always Steps to Reproduce: 1. Install X-Com 2. Run DosBox 3. Run X-Com Actual Results: dosbox CONFIG:Can't find config file dosbox.conf, using default settings Warning: Couldn't set audio fragment size ALSA lib seq_hw.c:446:(snd_seq_hw_open) open /dev/snd/seq failed: No such file or directory ALSA:Can't open sequencer MIDI:Opened device:none audio: Invalid argument Exit to error: Unhandled CPU opcode All errors except the last allow the program to continue, but when attempting to run any of the X-Com executables, the "Unhandled CPU opcode" error kills it. Expected Results: Ran the game. ;) Portage 2.0.49-r15 (default-x86-1.4, gcc-3.2.3, glibc-2.3.2-r1, 2.4.20-pfeifer-r1_pre11) ================================================================= System uname: 2.4.20-pfeifer-r1_pre11 i686 AMD Athlon(tm) XP 2500+ Gentoo Base System version 1.4.3.10p1 ccache version 2.3 [enabled] ACCEPT_KEYWORDS="x86" AUTOCLEAN="yes" CFLAGS="-march=athlon-xp -O3 -mfpmath=sse -pipe" CHOST="i686-pc-linux-gnu" COMPILER="gcc3" CONFIG_PROTECT="/etc /var/qmail/control /usr/kde/2/share/config /usr/kde/3/share/config /usr/X11R6/lib/X11/xkb /usr/kde/3.1/share/config /usr/share/texmf/tex/generic/config/ /usr/share/texmf/tex/platex/config/ /usr/share/config" CONFIG_PROTECT_MASK="/etc/gconf /etc/env.d" CXXFLAGS="-march=athlon-xp -O3 -mfpmath=sse -pipe" DISTDIR="/usr/portage/distfiles" FEATURES="sandbox autoaddcvs ccache fixpackages" GENTOO_MIRRORS="http://adelie.polymtl.ca/ http://mirror.tucdemonic.org/gentoo/ http://gentoo.noved.org/ ftp://gentoo.noved.org/ http://www.gtlib.cc.gatech.edu/pub/gentoo" MAKEOPTS="-j2" PKGDIR="/usr/portage/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/usr/portage" PORTDIR_OVERLAY="/usr/local/portage" SYNC="rsync://rsync.gentoo.org/gentoo-portage" USE="x86 oss apm avi crypt cups encode foomaticdb gif jpeg libg++ mad mikmod mpeg ncurses nls pdflib png quicktime spell truetype xml2 xmms xv zlib directfb gtkhtml berkdb slang readline arts tetex aalib nas bonobo svga ggi tcltk guile mysql X sdl gpm tcpd pam libwww ssl perl python esd imlib oggvorbis gnome gtk qt kde motif opengl gphoto2 cdr scanner 3dnow acpi acpi4linux apache2 autofs cjk clamav dga dnd doc dv dvb dvd dvdr evo faad ffmpeg flash gb gd geoip glut gnomedb gps gstreamer gtk2 imagemagick imap innodb ipv6 java jdepend joystick ladcca libgda lirc md5sum memlimit mldonkeypango mmx mng nocd oav offensive pda radeon S3TC samba slp snmp sqlite sse stencil-buffer tiff transcode type1 unicode usb v4l videos wmf xinerama xvid -alsa -gdbm video_cards_radeon"
http://dosbox.sourceforge.net/faq.php I direct you to question/answer 2. ;-) You can try dosbox-cvs to see if that works better for you. You might also want to try the non-protected-mode version of xcom. That one works fine for me, if a little slow.
Heh, actually, I discovered that if you install Microposes 1.4 patch things work beautifully. So, an FYI for everyone else, I guess.