windows 10 host
vbox Version 5.0.18 r106667
nvidia gtx 960

installed 16.04, nothing custom
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install xorg
startx on my user produces this log

[    79.021] 
X.Org X Server 1.18.3
Release Date: 2016-04-04
[    79.022] X Protocol Version 11, Revision 0
[    79.022] Build Operating System: Linux 3.13.0-85-generic x86_64 Ubuntu
[    79.023] Current Operating System: Linux ubu 4.4.0-21-generic #37-Ubuntu SMP Mon Apr 18 18:33:37 UTC 2016 x86_64
[    79.023] Kernel command line: BOOT_IMAGE=/vmlinuz-4.4.0-21-generic root=/dev/mapper/ubu--vg-root ro
[    79.025] Build Date: 07 April 2016  09:18:50AM
[    79.025] xorg-server 2:1.18.3-1ubuntu2 (For technical support please see http://www.ubuntu.com/support) 
[    79.026] Current version of pixman: 0.33.6
[    79.026] 	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
[    79.026] Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[    79.029] (==) Log file: "/home/collin/.local/share/xorg/Xorg.0.log", Time: Sat Apr 23 17:09:50 2016
[    79.029] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[    79.029] (==) No Layout section.  Using the first Screen section.
[    79.029] (==) No screen section available. Using defaults.
[    79.029] (**) |-->Screen "Default Screen Section" (0)
[    79.029] (**) |   |-->Monitor "<default monitor>"
[    79.030] (==) No monitor specified for screen "Default Screen Section".
	Using a default monitor configuration.
[    79.030] (==) Automatically adding devices
[    79.030] (==) Automatically enabling devices
[    79.030] (==) Automatically adding GPU devices
[    79.030] (==) Max clients allowed: 256, resource mask: 0x1fffff
[    79.030] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist.
[    79.030] 	Entry deleted from font path.
[    79.030] (WW) The directory "/usr/share/fonts/X11/100dpi/" does not exist.
[    79.030] 	Entry deleted from font path.
[    79.030] (WW) The directory "/usr/share/fonts/X11/75dpi/" does not exist.
[    79.030] 	Entry deleted from font path.
[    79.030] (WW) The directory "/usr/share/fonts/X11/100dpi" does not exist.
[    79.030] 	Entry deleted from font path.
[    79.030] (WW) The directory "/usr/share/fonts/X11/75dpi" does not exist.
[    79.030] 	Entry deleted from font path.
[    79.030] (==) FontPath set to:
	/usr/share/fonts/X11/misc,
	/usr/share/fonts/X11/Type1,
	built-ins
[    79.030] (==) ModulePath set to "/usr/lib/x86_64-linux-gnu/xorg/extra-modules,/usr/lib/xorg/extra-modules,/usr/lib/xorg/modules"
[    79.030] (II) The server relies on udev to provide the list of input devices.
	If no devices become available, reconfigure udev or disable AutoAddDevices.
[    79.030] (II) Loader magic: 0x55f71d918da0
[    79.030] (II) Module ABI versions:
[    79.030] 	X.Org ANSI C Emulation: 0.4
[    79.030] 	X.Org Video Driver: 20.0
[    79.030] 	X.Org XInput driver : 22.1
[    79.030] 	X.Org Server Extension : 9.0
[    79.031] (++) using VT number 1

[    79.049] (II) systemd-logind: took control of session /org/freedesktop/login1/session/_31
[    79.049] (II) xfree86: Adding drm device (/dev/dri/card0)
[    79.049] (II) systemd-logind: got fd for /dev/dri/card0 226:0 fd 8 paused 0
[    79.054] (--) PCI:*(0:0:2:0) 80ee:beef:0000:0000 rev 0, Mem @ 0xe0000000/16777216
[    79.054] (II) LoadModule: "glx"
[    79.054] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[    79.055] (II) Module glx: vendor="X.Org Foundation"
[    79.055] 	compiled for 1.18.3, module version = 1.0.0
[    79.055] 	ABI class: X.Org Server Extension, version 9.0
[    79.055] (==) AIGLX enabled
[    79.055] (==) Matched vboxvideo as autoconfigured driver 0
[    79.055] (==) Matched vboxvideo as autoconfigured driver 1
[    79.055] (==) Matched modesetting as autoconfigured driver 2
[    79.055] (==) Matched fbdev as autoconfigured driver 3
[    79.055] (==) Matched vesa as autoconfigured driver 4
[    79.055] (==) Assigned the driver to the xf86ConfigLayout
[    79.055] (II) LoadModule: "vboxvideo"
[    79.055] (WW) Warning, couldn't open module vboxvideo
[    79.055] (II) UnloadModule: "vboxvideo"
[    79.055] (II) Unloading vboxvideo
[    79.055] (EE) Failed to load module "vboxvideo" (module does not exist, 0)
[    79.055] (II) LoadModule: "modesetting"
[    79.055] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[    79.055] (II) Module modesetting: vendor="X.Org Foundation"
[    79.055] 	compiled for 1.18.3, module version = 1.18.3
[    79.055] 	Module class: X.Org Video Driver
[    79.055] 	ABI class: X.Org Video Driver, version 20.0
[    79.055] (II) LoadModule: "fbdev"
[    79.055] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so
[    79.055] (II) Module fbdev: vendor="X.Org Foundation"
[    79.055] 	compiled for 1.18.1, module version = 0.4.4
[    79.055] 	Module class: X.Org Video Driver
[    79.055] 	ABI class: X.Org Video Driver, version 20.0
[    79.055] (II) LoadModule: "vesa"
[    79.056] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so
[    79.056] (II) Module vesa: vendor="X.Org Foundation"
[    79.056] 	compiled for 1.18.1, module version = 2.3.4
[    79.056] 	Module class: X.Org Video Driver
[    79.056] 	ABI class: X.Org Video Driver, version 20.0
[    79.056] (==) Matched vboxvideo as autoconfigured driver 0
[    79.056] (==) Matched vboxvideo as autoconfigured driver 1
[    79.056] (==) Matched modesetting as autoconfigured driver 2
[    79.056] (==) Matched fbdev as autoconfigured driver 3
[    79.056] (==) Matched vesa as autoconfigured driver 4
[    79.056] (==) Assigned the driver to the xf86ConfigLayout
[    79.056] (II) LoadModule: "vboxvideo"
[    79.056] (WW) Warning, couldn't open module vboxvideo
[    79.056] (II) UnloadModule: "vboxvideo"
[    79.056] (II) Unloading vboxvideo
[    79.056] (EE) Failed to load module "vboxvideo" (module does not exist, 0)
[    79.056] (II) LoadModule: "modesetting"
[    79.056] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[    79.056] (II) Module modesetting: vendor="X.Org Foundation"
[    79.056] 	compiled for 1.18.3, module version = 1.18.3
[    79.056] 	Module class: X.Org Video Driver
[    79.056] 	ABI class: X.Org Video Driver, version 20.0
[    79.056] (II) UnloadModule: "modesetting"
[    79.056] (II) Unloading modesetting
[    79.056] (II) Failed to load module "modesetting" (already loaded, 0)
[    79.056] (II) LoadModule: "fbdev"
[    79.056] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so
[    79.056] (II) Module fbdev: vendor="X.Org Foundation"
[    79.056] 	compiled for 1.18.1, module version = 0.4.4
[    79.056] 	Module class: X.Org Video Driver
[    79.056] 	ABI class: X.Org Video Driver, version 20.0
[    79.056] (II) UnloadModule: "fbdev"
[    79.056] (II) Unloading fbdev
[    79.056] (II) Failed to load module "fbdev" (already loaded, 0)
[    79.056] (II) LoadModule: "vesa"
[    79.056] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so
[    79.056] (II) Module vesa: vendor="X.Org Foundation"
[    79.056] 	compiled for 1.18.1, module version = 2.3.4
[    79.056] 	Module class: X.Org Video Driver
[    79.056] 	ABI class: X.Org Video Driver, version 20.0
[    79.056] (II) UnloadModule: "vesa"
[    79.056] (II) Unloading vesa
[    79.056] (II) Failed to load module "vesa" (already loaded, 0)
[    79.056] (II) modesetting: Driver for Modesetting Kernel Drivers: kms
[    79.056] (II) FBDEV: driver for framebuffer: fbdev
[    79.056] (II) VESA: driver for VESA chipsets: vesa
[    79.056] xf86EnableIOPorts: failed to set IOPL for I/O (Operation not permitted)
[    79.057] (WW) Falling back to old probe method for modesetting
[    79.057] (II) Loading sub module "fbdevhw"
[    79.057] (II) LoadModule: "fbdevhw"
[    79.057] (II) Loading /usr/lib/xorg/modules/libfbdevhw.so
[    79.057] (II) Module fbdevhw: vendor="X.Org Foundation"
[    79.057] 	compiled for 1.18.3, module version = 0.0.2
[    79.057] 	ABI class: X.Org Video Driver, version 20.0
[    79.057] (EE) open /dev/fb0: No such file or directory
[    79.057] (II) Loading sub module "fbdevhw"
[    79.057] (II) LoadModule: "fbdevhw"
[    79.057] (II) Loading /usr/lib/xorg/modules/libfbdevhw.so
[    79.057] (II) Module fbdevhw: vendor="X.Org Foundation"
[    79.057] 	compiled for 1.18.3, module version = 0.0.2
[    79.057] 	ABI class: X.Org Video Driver, version 20.0
[    79.057] (EE) open /dev/fb0: No such file or directory
[    79.057] (WW) Falling back to old probe method for fbdev
[    79.057] (II) Loading sub module "fbdevhw"
[    79.057] (II) LoadModule: "fbdevhw"
[    79.057] (II) Loading /usr/lib/xorg/modules/libfbdevhw.so
[    79.057] (II) Module fbdevhw: vendor="X.Org Foundation"
[    79.057] 	compiled for 1.18.3, module version = 0.0.2
[    79.057] 	ABI class: X.Org Video Driver, version 20.0
[    79.057] (EE) open /dev/fb0: No such file or directory
[    79.057] (EE) open /dev/fb0: No such file or directory
[    79.057] (WW) VGA arbiter: cannot open kernel arbiter, no multi-card support
[    79.057] (EE) Screen 0 deleted because of no matching config section.
[    79.057] (II) UnloadModule: "modesetting"
[    79.057] (EE) Screen 0 deleted because of no matching config section.
[    79.057] (II) UnloadModule: "modesetting"
[    79.057] (EE) Screen 0 deleted because of no matching config section.
[    79.057] (II) UnloadModule: "fbdev"
[    79.057] (II) UnloadSubModule: "fbdevhw"
[    79.057] (EE) Screen 0 deleted because of no matching config section.
[    79.057] (II) UnloadModule: "fbdev"
[    79.057] (II) UnloadSubModule: "fbdevhw"
[    79.057] (II) UnloadSubModule: "fbdevhw"
[    79.057] (II) Loading sub module "vbe"
[    79.057] (II) LoadModule: "vbe"
[    79.058] (II) Loading /usr/lib/xorg/modules/libvbe.so
[    79.058] (II) Module vbe: vendor="X.Org Foundation"
[    79.058] 	compiled for 1.18.3, module version = 1.1.0
[    79.058] 	ABI class: X.Org Video Driver, version 20.0
[    79.058] (II) Loading sub module "int10"
[    79.058] (II) LoadModule: "int10"
[    79.058] (II) Loading /usr/lib/xorg/modules/libint10.so
[    79.058] (II) Module int10: vendor="X.Org Foundation"
[    79.058] 	compiled for 1.18.3, module version = 1.0.0
[    79.058] 	ABI class: X.Org Video Driver, version 20.0
[    79.058] (II) VESA(0): initializing int10
[    79.058] (EE) VESA(0): Cannot read int vect
[    79.058] (II) UnloadModule: "vesa"
[    79.058] (II) UnloadSubModule: "int10"
[    79.058] (II) Unloading int10
[    79.058] (II) UnloadSubModule: "vbe"
[    79.058] (II) Unloading vbe
[    79.058] (EE) Screen(s) found, but none have a usable configuration.
[    79.058] (EE) 
Fatal server error:
[    79.058] (EE) no screens found(EE) 
[    79.058] (EE) 
Please consult the The X.Org Foundation support 
	 at http://wiki.x.org
 for help. 
[    79.058] (EE) Please also check the log file at "/home/collin/.local/share/xorg/Xorg.0.log" for additional information.
[    79.058] (EE) 
[    79.068] (EE) Server terminated with error (1). Closing log file.


xinit produces this log:

[   532.780] 
X.Org X Server 1.18.3
Release Date: 2016-04-04
[   532.781] X Protocol Version 11, Revision 0
[   532.782] Build Operating System: Linux 3.13.0-85-generic x86_64 Ubuntu
[   532.783] Current Operating System: Linux ubu 4.4.0-21-generic #37-Ubuntu SMP Mon Apr 18 18:33:37 UTC 2016 x86_64
[   532.784] Kernel command line: BOOT_IMAGE=/vmlinuz-4.4.0-21-generic root=/dev/mapper/ubu--vg-root ro
[   532.785] Build Date: 07 April 2016  09:18:50AM
[   532.786] xorg-server 2:1.18.3-1ubuntu2 (For technical support please see http://www.ubuntu.com/support) 
[   532.787] Current version of pixman: 0.33.6
[   532.789] 	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
[   532.789] Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[   532.793] (==) Log file: "/home/collin/.local/share/xorg/Xorg.0.log", Time: Sat Apr 23 17:17:24 2016
[   532.794] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[   532.794] (==) No Layout section.  Using the first Screen section.
[   532.794] (==) No screen section available. Using defaults.
[   532.794] (**) |-->Screen "Default Screen Section" (0)
[   532.794] (**) |   |-->Monitor "<default monitor>"
[   532.794] (==) No monitor specified for screen "Default Screen Section".
	Using a default monitor configuration.
[   532.794] (==) Automatically adding devices
[   532.794] (==) Automatically enabling devices
[   532.794] (==) Automatically adding GPU devices
[   532.794] (==) Max clients allowed: 256, resource mask: 0x1fffff
[   532.795] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist.
[   532.795] 	Entry deleted from font path.
[   532.795] (WW) The directory "/usr/share/fonts/X11/100dpi/" does not exist.
[   532.795] 	Entry deleted from font path.
[   532.795] (WW) The directory "/usr/share/fonts/X11/75dpi/" does not exist.
[   532.795] 	Entry deleted from font path.
[   532.795] (WW) The directory "/usr/share/fonts/X11/100dpi" does not exist.
[   532.795] 	Entry deleted from font path.
[   532.795] (WW) The directory "/usr/share/fonts/X11/75dpi" does not exist.
[   532.795] 	Entry deleted from font path.
[   532.795] (==) FontPath set to:
	/usr/share/fonts/X11/misc,
	/usr/share/fonts/X11/Type1,
	built-ins
[   532.795] (==) ModulePath set to "/usr/lib/x86_64-linux-gnu/xorg/extra-modules,/usr/lib/xorg/extra-modules,/usr/lib/xorg/modules"
[   532.795] (II) The server relies on udev to provide the list of input devices.
	If no devices become available, reconfigure udev or disable AutoAddDevices.
[   532.795] (II) Loader magic: 0x55952fba2da0
[   532.795] (II) Module ABI versions:
[   532.795] 	X.Org ANSI C Emulation: 0.4
[   532.795] 	X.Org Video Driver: 20.0
[   532.795] 	X.Org XInput driver : 22.1
[   532.795] 	X.Org Server Extension : 9.0
[   532.815] (II) systemd-logind: took control of session /org/freedesktop/login1/session/_31
[   532.815] (II) xfree86: Adding drm device (/dev/dri/card0)
[   532.815] (II) systemd-logind: got fd for /dev/dri/card0 226:0 fd 8 paused 0
[   532.819] (--) PCI:*(0:0:2:0) 80ee:beef:0000:0000 rev 0, Mem @ 0xe0000000/16777216
[   532.819] (II) LoadModule: "glx"
[   532.819] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[   532.820] (II) Module glx: vendor="X.Org Foundation"
[   532.820] 	compiled for 1.18.3, module version = 1.0.0
[   532.820] 	ABI class: X.Org Server Extension, version 9.0
[   532.820] (==) AIGLX enabled
[   532.820] (==) Matched vboxvideo as autoconfigured driver 0
[   532.820] (==) Matched vboxvideo as autoconfigured driver 1
[   532.820] (==) Matched modesetting as autoconfigured driver 2
[   532.820] (==) Matched fbdev as autoconfigured driver 3
[   532.820] (==) Matched vesa as autoconfigured driver 4
[   532.820] (==) Assigned the driver to the xf86ConfigLayout
[   532.820] (II) LoadModule: "vboxvideo"
[   532.820] (WW) Warning, couldn't open module vboxvideo
[   532.820] (II) UnloadModule: "vboxvideo"
[   532.820] (II) Unloading vboxvideo
[   532.820] (EE) Failed to load module "vboxvideo" (module does not exist, 0)
[   532.820] (II) LoadModule: "modesetting"
[   532.820] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[   532.820] (II) Module modesetting: vendor="X.Org Foundation"
[   532.820] 	compiled for 1.18.3, module version = 1.18.3
[   532.820] 	Module class: X.Org Video Driver
[   532.820] 	ABI class: X.Org Video Driver, version 20.0
[   532.820] (II) LoadModule: "fbdev"
[   532.820] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so
[   532.820] (II) Module fbdev: vendor="X.Org Foundation"
[   532.820] 	compiled for 1.18.1, module version = 0.4.4
[   532.820] 	Module class: X.Org Video Driver
[   532.820] 	ABI class: X.Org Video Driver, version 20.0
[   532.820] (II) LoadModule: "vesa"
[   532.821] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so
[   532.821] (II) Module vesa: vendor="X.Org Foundation"
[   532.821] 	compiled for 1.18.1, module version = 2.3.4
[   532.821] 	Module class: X.Org Video Driver
[   532.821] 	ABI class: X.Org Video Driver, version 20.0
[   532.821] (==) Matched vboxvideo as autoconfigured driver 0
[   532.821] (==) Matched vboxvideo as autoconfigured driver 1
[   532.821] (==) Matched modesetting as autoconfigured driver 2
[   532.821] (==) Matched fbdev as autoconfigured driver 3
[   532.821] (==) Matched vesa as autoconfigured driver 4
[   532.821] (==) Assigned the driver to the xf86ConfigLayout
[   532.821] (II) LoadModule: "vboxvideo"
[   532.821] (WW) Warning, couldn't open module vboxvideo
[   532.821] (II) UnloadModule: "vboxvideo"
[   532.821] (II) Unloading vboxvideo
[   532.821] (EE) Failed to load module "vboxvideo" (module does not exist, 0)
[   532.821] (II) LoadModule: "modesetting"
[   532.821] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[   532.821] (II) Module modesetting: vendor="X.Org Foundation"
[   532.821] 	compiled for 1.18.3, module version = 1.18.3
[   532.821] 	Module class: X.Org Video Driver
[   532.821] 	ABI class: X.Org Video Driver, version 20.0
[   532.821] (II) UnloadModule: "modesetting"
[   532.821] (II) Unloading modesetting
[   532.821] (II) Failed to load module "modesetting" (already loaded, 0)
[   532.821] (II) LoadModule: "fbdev"
[   532.821] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so
[   532.821] (II) Module fbdev: vendor="X.Org Foundation"
[   532.821] 	compiled for 1.18.1, module version = 0.4.4
[   532.821] 	Module class: X.Org Video Driver
[   532.821] 	ABI class: X.Org Video Driver, version 20.0
[   532.821] (II) UnloadModule: "fbdev"
[   532.821] (II) Unloading fbdev
[   532.821] (II) Failed to load module "fbdev" (already loaded, 0)
[   532.821] (II) LoadModule: "vesa"
[   532.821] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so
[   532.821] (II) Module vesa: vendor="X.Org Foundation"
[   532.821] 	compiled for 1.18.1, module version = 2.3.4
[   532.821] 	Module class: X.Org Video Driver
[   532.821] 	ABI class: X.Org Video Driver, version 20.0
[   532.821] (II) UnloadModule: "vesa"
[   532.821] (II) Unloading vesa
[   532.821] (II) Failed to load module "vesa" (already loaded, 0)
[   532.821] (II) modesetting: Driver for Modesetting Kernel Drivers: kms
[   532.821] (II) FBDEV: driver for framebuffer: fbdev
[   532.821] (II) VESA: driver for VESA chipsets: vesa
[   532.821] (EE) 
Fatal server error:
[   532.821] (EE) parse_vt_settings: Cannot open /dev/tty0 (No such file or directory)
[   532.821] (EE) 
[   532.821] (EE) 
Please consult the The X.Org Foundation support 
	 at http://wiki.x.org
 for help. 
[   532.821] (EE) Please also check the log file at "/home/collin/.local/share/xorg/Xorg.0.log" for additional information.
[   532.821] (EE) 


sudo startx

works!

appears my user is missing some permissions, or maybe X is not configured properly to use a tty w/ more lose permissions.