I've tried downgrading mesa, mesa-libgl, xorg-server, xorg-server-common and sdl2. I've also made sure it is using the correct mame.ini file.
Latest log file seems to show it's trying to do the right mode:
SwitchRes: v0.015m, Monitor: lcd, Orientation: horizontal, Modeline generation: disabled
SwitchRes: Using default vfreq range for LCD 59.000000-61.000000
SwitchRes: Found output connector 'DVI-I-1'
SwitchRes: Creating automatic specs for LCD based on VESA GTF
SwitchRes: Monitor range 73278.00-75762.00,59.00-61.00,0.696,1.044,1.740,0.013,0.040,0.510,0,1,1200,1200,0,0
SwitchRes: -resolution was set at command line or in .ini file as 1600x1200@60
SwitchRes: Entering switchres_modeline_setup
SwitchRes: v0.015m:[pacman] Calculating best video mode for 224x288@60.606060 orientation: rotated
SwitchRes: [1600]x[1200]_[60=60.000000Hz]
rng(0): 1600 x1200_60.000000p 0.000000 [integ] scale(4, 4, 1) diff(0.44, 5.48, -0.6061) ratio(7.143, 4.167)
SwitchRes: [pacman] (1) vertical (224x288@60.606060)->(1600x1200@60.000000)
rng(0): 1600 x1200_60.000000p 0.000000 [integ] scale(4, 4, 1) diff(0.44, 5.48, -0.6061) ratio(7.143, 4.167)
SwitchRes: Setting option -rotate
SwitchRes: Setting option -noror
SwitchRes: Setting option -noautoror
SwitchRes: Setting option -norol
SwitchRes: Setting option -noautorol
SwitchRes: Setting option -noblack_frame_insertion
SwitchRes: Setting option -multithreading
SwitchRes: Setting option -nosyncrefresh
SwitchRes: Setting option -nowaitvsync
SwitchRes: Setting option -keepaspect
SwitchRes: Setting option -nounevenstretch
SwitchRes: Setting option -nofilter
SwitchRes: Setting option -prescale 3
Available videodrivers: x11 wayland dummy
Current Videodriver: x11
Display #0
Renderdrivers:
opengl (0x0)
opengles2 (0x0)
opengles (0x0)
software (0x0)
Available audio drivers:
pulseaudio
alsa
dsp
disk
dummy
Build version: 0.171 (May 1 2016)
Build architecure:
Build defines 1: SDLMAME_UNIX=1 SDLMAME_X11=1 SDLMAME_LINUX=1
Build defines 1: LSB_FIRST=1 PTR64=1 SYNC_IMPLEMENTATION=tc
SDL/OpenGL defines: SDL_COMPILEDVERSION=2003 USE_OPENGL=1
Compiler defines A: __GNUC__=5 __GNUC_MINOR__=3 __GNUC_PATCHLEVEL__=0 __VERSION__="5.3.0"
Compiler defines B: __amd64__=1 __x86_64__=1 __unix__=1
Compiler defines C: __USE_FORTIFY_LEVEL=0
Enter init_monitors
Adding monitor screen0 (1600 x 1200)
Leave init_monitors
Enter sdlwindow_init
Using SDL multi-window OpenGL driver (SDL 2.0+)
/dev/dri/card0 successfully opened
Hints:
SDL_FRAMEBUFFER_ACCELERATION (null)
SDL_RENDER_DRIVER (null)
SDL_RENDER_OPENGL_SHADERS (null)
SDL_RENDER_SCALE_QUALITY (null)
SDL_RENDER_VSYNC (null)
SDL_VIDEO_X11_XVIDMODE (null)
SDL_VIDEO_X11_XINERAMA (null)
SDL_VIDEO_X11_XRANDR (null)
SDL_GRAB_KEYBOARD (null)
SDL_VIDEO_MINIMIZE_ON_FOCUS_LOSS (null)
SDL_IOS_IDLE_TIMER_DISABLED (null)
SDL_IOS_ORIENTATIONS (null)
SDL_XINPUT_ENABLED (null)
SDL_GAMECONTROLLERCONFIG (null)
SDL_JOYSTICK_ALLOW_BACKGROUND_EVENTS (null)
SDL_ALLOW_TOPMOST (null)
SDL_TIMER_RESOLUTION (null)
SDL_RENDER_DIRECT3D_THREADSAFE (null)
SDL_VIDEO_ALLOW_SCREENSAVER (null)
SDL_ACCELEROMETER_AS_JOYSTICK (null)
SDL_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK (null)
SDL_VIDEO_WIN_D3DCOMPILER (null)
SDL_VIDEO_WINDOW_SHARE_PIXEL_FORMAT (null)
SDL_VIDEO_MAC_FULLSCREEN_SPACES (null)
SDL_MOUSE_RELATIVE_MODE_WARP (null)
SDL_HINT_RENDER_DIRECT3D11_DEBUG (null)
SDL_VIDEO_HIGHDPI_DISABLED (null)
SDL_HINT_WINRT_PRIVACY_POLICY_URL (null)
SDL_HINT_WINRT_PRIVACY_POLICY_LABEL (null)
SDL_HINT_WINRT_HANDLE_BACK_BUTTON (null)
Leave sdlwindow_init
Enter sdl_info::create
OpenGL: nouveau
OpenGL: Gallium 0.4 on NVC8
OpenGL: 3.0 Mesa 11.2.1
OpenGL: texture rectangle supported
OpenGL: non-power-of-2 textures supported (new method)
OpenGL: vertex buffer supported
OpenGL: pixel buffers supported
OpenGL: framebuffer object supported
OpenGL: GLSL supported, but disabled
OpenGL: max texture size 16384 x 16384
Leave renderer_ogl::create
Keyboard: Start initialization
Input: Adding Kbd #0: System keyboard
Keyboard: Registered System keyboard
Keyboard: End initialization
Mouse: Start initialization
Input: Adding Mouse #0: System mouse
Mouse: Registered System mouse
Mouse: End initialization
Joystick: Start initialization
Input: Adding Joy #0: Ultimarc IPAC 2 Ultimarc IPAC 2
Joystick: Ultimarc IPAC 2 Ultimarc IPAC 2
Joystick: ... 4 axes, 32 buttons 1 hats 0 balls
Joystick: ... Physical id 0 mapped to logical id 1
Joystick: End initialization
output: unable to open output notifier file /tmp/sdlmame_out
Audio: Start initialization
Audio: Driver is pulseaudio
Audio: frequency: 48000, channels: 2, samples: 256
sdl_create_buffers: creating stream buffer of 18432 bytes
Audio: End initialization
Region ':maincpu' created
Region ':gfx1' created
Region ':proms' created
Region ':namco' created
Starting Pac-Man (Midway) ':'
Optional shared pointer 'patched_opcodes' not found
Optional shared pointer 'rocktrv2_prot' not found
Optional shared pointer 's2650_tileram' not found
Optional shared pointer 's2650_spriteram' not found
(missing dependencies; rescheduling)
Starting Z80 ':maincpu'
Starting gfxdecode ':gfxdecode'
Starting palette ':palette'
Starting Video Screen ':screen'
Starting Speaker ':mono'
(missing dependencies; rescheduling)
Starting Namco ':namco'
Starting Pac-Man (Midway) ':'
Optional shared pointer 'patched_opcodes' not found
Optional shared pointer 'rocktrv2_prot' not found
Optional shared pointer 's2650_tileram' not found
Optional shared pointer 's2650_spriteram' not found
(missing dependencies; rescheduling)
Starting Speaker ':mono'
Starting Pac-Man (Midway) ':'
Optional shared pointer 'patched_opcodes' not found
Optional shared pointer 'rocktrv2_prot' not found
Optional shared pointer 's2650_tileram' not found
Optional shared pointer 's2650_spriteram' not found
Mameinfo.dat games found = 9501
Mameinfo.dat drivers found = 1330
Rev = v0.172
Command.dat games found = 632
Messinfo.dat games found = 2351
Messinfo.dat drivers found = 672
Rev = v0.171
Sysinfo.dat games found = 735
Rev = 2012-09-11.
History.dat games found = 26946
History.dat softwares found = 52879
Rev = 1.72
Here is a list of packages that have been updated recently:
2016-04-30 17:59:16 tzdata
2016-04-30 17:59:17 fontconfig
2016-04-30 17:59:17 gdk-pixbuf2
2016-04-30 17:59:17 glib2
2016-04-30 17:59:17 gtk-update-icon-cache
2016-04-30 17:59:17 harfbuzz
2016-04-30 17:59:21 cracklib
2016-04-30 17:59:21 elfutils
2016-04-30 17:59:21 iptables
2016-04-30 17:59:21 libelf
2016-04-30 17:59:21 libmnl
2016-04-30 17:59:21 libnftnl
2016-04-30 17:59:21 libutil-linux
2016-04-30 17:59:21 util-linux
2016-04-30 17:59:22 libxml2
2016-04-30 17:59:22 texinfo
2016-04-30 17:59:23 librsvg
2016-04-30 17:59:23 mesa-libgl
2016-04-30 17:59:23 pango
2016-04-30 17:59:24 adwaita-icon-theme
2016-04-30 17:59:24 alsa-lib
2016-04-30 17:59:24 alsa-utils
2016-04-30 17:59:24 archlinux-keyring
2016-04-30 17:59:26 inputproto
2016-04-30 17:59:31 at-spi2-atk
2016-04-30 17:59:31 at-spi2-core
2016-04-30 17:59:31 atk
2016-04-30 17:59:31 btrfs-progs
2016-04-30 17:59:31 sqlite
2016-04-30 17:59:32 colord
2016-04-30 17:59:32 dconf
2016-04-30 17:59:32 desktop-file-utils
2016-04-30 17:59:32 device-mapper
2016-04-30 17:59:32 dhclient
2016-04-30 17:59:32 dhcp
2016-04-30 17:59:32 dhcpcd
2016-04-30 17:59:32 f2fs-tools
2016-04-30 17:59:32 iproute2
2016-04-30 17:59:33 ffmpeg
2016-04-30 17:59:33 libavc1394
2016-04-30 17:59:33 libiec61883
2016-04-30 17:59:33 libraw1394
2016-04-30 17:59:34 glib-networking
2016-04-30 17:59:34 gsettings-desktop-schemas
2016-04-30 17:59:34 json-glib
2016-04-30 17:59:34 libcups
2016-04-30 17:59:34 libsoup
2016-04-30 17:59:34 libxkbcommon
2016-04-30 17:59:34 shared-mime-info
2016-04-30 17:59:34 wayland-protocols
2016-04-30 17:59:35 gtk3
2016-04-30 17:59:36 gtk2
2016-04-30 17:59:37 icu
2016-04-30 17:59:41 firefox
2016-04-30 17:59:41 flashrom
2016-04-30 17:59:41 fltk
2016-04-30 17:59:41 glib2-docs
2016-04-30 17:59:41 grep
2016-04-30 17:59:41 imlib2
2016-04-30 17:59:41 xdg-utils
2016-04-30 17:59:42 iputils
2016-04-30 17:59:42 libinput
2016-04-30 17:59:43 libx86emu
2016-04-30 17:59:43 libxkbcommon-x11
2016-04-30 17:59:46 linux-firmware
2016-04-30 17:59:52 linux
2016-04-30 18:00:07 linux-docs
2016-04-30 18:00:09 linux-headers
2016-04-30 18:00:13 linux-lts
2016-04-30 18:00:27 linux-lts-docs
2016-04-30 18:00:28 linux-lts-headers
2016-04-30 18:00:28 logrotate
2016-04-30 18:00:29 lvm2
2016-04-30 18:00:31 qt4
2016-04-30 18:00:32 qt5-base
2016-04-30 18:00:37 sqlite-doc
2016-04-30 18:00:37 sqlite-tcl
2016-04-30 18:00:38 syslinux
2016-04-30 18:00:38 unzip
2016-04-30 18:00:38 vte-common
2016-04-30 18:00:38 xf86-input-evdev
2016-04-30 18:00:38 xorg-server
2016-04-30 18:00:38 xorg-server-common
2016-04-30 18:00:38 xorg-xinit
2016-05-01 18:06:58 file
2016-05-01 18:06:58 gzip
2016-05-01 18:06:59 git
2016-05-01 18:06:59 libtasn1
2016-05-01 18:06:59 nettle
2016-05-01 18:07:00 gnutls
2016-05-01 18:07:00 libdrm
2016-05-01 18:07:00 libgcrypt
2016-05-01 18:07:00 libgpg-error
2016-05-01 18:07:00 nano
2016-05-01 18:07:26 sdl2
2016-05-01 18:15:18 pacutils
2016-05-02 22:06:15 mesa
2016-05-02 22:25:18 fuse
2016-05-02 22:25:19 ntp
2016-05-02 22:25:19 pacman-mirrorlist