Ubuntu 15.04 flashes log-in screen then black

A few weeks ago, I built a desktop and installed Ubuntu 15.04 and have been battling with it ever since. There seems to be an issue with the compatibility of the NVIDIA drivers and Ubuntu.

(After weeks of struggling with various black/purple screens, toggling nomodeset, blacklisting nouveau, and restarting lightdm/trying gdm, returning my GTX960 for a GTX750TI, installing Ubuntu 14.04 and 14.10, login loops, and a few other things I'm sure I forgot, I have the following minimal example.)

1. I create a boot USB with Ubuntu 15.04.
2. I select "Install Ubuntu" (note that I must edit the options for this, changing "quiet splash" to "quiet splash nomodeset" or else it doesn't work).
3. After installing Ubuntu, I am asked to restart. I can boot in recovery mode (although the resolution is strange), but not normally.
4. At this point, I have tried various things (reinstall nvidia drivers, permanently add nomodeset to boot options, etc.), most of which end up leading to the need to reinstall Ubuntu from scratch due to inability to see anything without removing the graphics card and plugging the monitor into the motherboard.

I have just completed the first 3 steps, which are by now muscle memory, and am begging for suggestions on a new step 4.

EDIT: I have tried the steps here (which led me to the nomodeset option that allows me to see the screen while I install Ubuntu) but when I update the NVIDIA drivers (I have tried both the proprietary and non-proprietary versions, many different version numbers), this leads me to other problems. Most often, it is a login loop, but occasionally it is a black/purple screen. When I follow the suggested to address the login loop, this invariably leads me back to a blank screen and I then reinstall Ubuntu.

$ sudo lshw -C video
  *-display UNCLAIMED     
       description: VGA compatible controller
       product: GM107 [GeForce GTX 750 Ti]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a2
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress vga_controller bus_master cap_list
       configuration: latency=0
       resources: memory:f6000000-f6ffffff memory:e0000000-efffffff memory:f0000000-f1ffffff ioport:e000(size=128) memory:f7000000-f707ffff

Update: installing bumblebee allows me to escape the login loop. The resolution of my monitor still doesn't look right, and I have to click out of about a dozen "Report system problem" boxes.

Edit: My xorg.log is here.

I too built a desktop, and used the 750Ti. I had the exact problem that the OP has, and I can personally testify that the below worked for me. I don't have a ton of time, so I'll have to summarize. When in doubt, Google is your friend.

1. Go to NVIDIA's website from another PC and download the appropriate driver to a USB drive.

2. Plug this USB drive into your desktop and boot. At the login screen, enter runlevel 2 by pressing CTRL+ALT+2

3. Now you will be in a terminal (fun times!). Login using your account.

4. Kill lightdm.

5. Mount your USB drive and un-tar the driver.

6. Run the driver installer. If there are no errors during installation, then reboot. The login loop should now be gone.

This makes it sound simple, but unfortunately, it is actually pretty difficult. It took me four tries to get it right.

Let me know how this works for you!