Ok, the first three steps came back saying there were 0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
Got to Ctrl + Alt + F3
After that the screen goes black, but there was no console or text and nowhere to type raxial or the password, so kind of got stuck there. 
Does
Ctrl+Alt+F1
or
Ctrl+Alt+F2
or
Ctrl+Alt+F4
or
Ctrl+Alt+F5
Give you a black background with text ?
if not … what happens if you do Ctrl+Alt+F3, the hold the A key for a while … does a bunch of A’s eventually appear … jjust trying to figure out if the text is there, but off screen.
BTW,
Ctrl+Alt+F7
will bring you back to your desktop
All of those give just black background, no text.
Ctrl+Alt+F3 then holding A = black screen on which nothing shows at all.
Weird.
OK, let’s do it the PPA way then…
run these commands in sequence:
sudo apt-get install ppa-purge
then
sudo add-apt-repository ppa:xorg-edgers/ppa
then
sudo apt-get update
then
sudo apt-get upgrade
then
sudo apt-get dist-upgrade
then reboot
Once rebooted, does “Driver Manager” offer you any drivers ?
EDIT: Just a thought - might this issue no longer be an issue if I were using a different version/flavour Linux?
I did all of that, reboot, click Driver Manager, enter password, nothing happens/opens.
Here’s what came up in Terminal:
raxial@Skynet ~ $ sudo apt-get install ppa-purge
[sudo] password for raxial:
Reading package lists… Done
Building dependency tree
Reading state information… Done
E: Unable to locate package ppa-purge
raxial@Skynet ~ $ sudo add-apt-repository ppa:xorg-edgers/ppa
You are about to add the following PPA to your system:
== Xorg packages fresh from git ==
Currently supported releases are Trusty/14.04, and Utopic/14.10
xserver 1.16 is now in for utopic, beware that fglrx does not support it yet!
WARNING: Do not use this PPA with the precise X backport stacks, aka if you fresh install of 12.04.2 or newer. You can switch back to a compatible one by installing xserver-xorg-lts-precise instead if you do want to use these packages but horrible things will happen if you don’t.
To revert to official packages, install the ppa-purge package and run “sudo ppa-purge xorg-edgers”.
== Important notice ==
This PPA is currently meant to be used as a whole. Please do not individually install packages from it, add it to your sources and let your package manager pull in every update. The packages here build against each other and compile different features based on whats available at build time. Do not assume that because it lets you install a DDX with just the driver and libdrm update that it will work. These packages are made with scripts that use the the current packages as the base, so some dependencies can be wrong and your package manager will not resolve that for you. If you want to individually install something from here, grab the source and rebuild it in your current environment instead.
** Please do not publish instructions for how to install from this archive without linking to this page! Anyone using packages from this archive is expected to read this page first and it is recommended to check back occasionally for notice on problems that may arise. **
More info: xorg-edgers fresh X crack : “xorg crack pushers” team
Press [ENTER] to continue or ctrl-c to cancel adding it
Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --homedir /tmp/tmp.O6suH1n1BV --no-auto-check-trustdb --trust-model always --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 8844C542
gpg: requesting key 8844C542 from hkp server keyserver.ubuntu.com
gpg: key 8844C542: public key “Launchpad PPA for xorg crack pushers” imported
gpg: Total number processed: 1
gpg: imported: 1 (RSA: 1)
raxial@Skynet ~ $ sudo apt-get upgrade
Reading package lists… Error!
E: Type ‘Linux x64 (AMD64/EM64T) Display Driver | 340.17 | Linux 64-bit | NVIDIA is not known on line 1 in source list /etc/apt/sources.list.d/additional-repositories.list
E: The list of sources could not be read.
E: The package lists or status file could not be parsed or opened.
raxial@Skynet ~ $ sudo apt-get dist-upgrade
Reading package lists… Done
Building dependency tree
Reading state information… Done
Calculating upgrade… Done
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
raxial@Skynet ~ $
[EDIT]
Before doing what’s listed below, can you post the output from:
cat /etc/apt/sources.list.d/additional-repositories.list
[END EDIT]
you missed a command
Run:
sudo apt-get update
then
sudo apt-get upgrade
then
sudo apt-get dist-upgrade
then REBOOT
then does Driver Mnager offer anything ?
Just a thought - might this issue no longer be an issue if I were using a different version/flavour Linux?
NO … I doubt if ANY flavour will have the 340 drivers in their repos yet.
Though a different distro “might” give you the console properly … but so might this one once we get the drivers loaded 
Okay, that brings this: cat /etc/apt/sources.list.d/additional-repositories.list
…
Then this:
raxial@Skynet ~ $ sudo apt-get update
[sudo] password for raxial:
E: Type ‘Linux x64 (AMD64/EM64T) Display Driver | 340.17 | Linux 64-bit | NVIDIA is not known on line 1 in source list /etc/apt/sources.list.d/additional-repositories.list
E: The list of sources could not be read.
raxial@Skynet ~ $ sudo apt-get upgrade
Reading package lists… Done
Building dependency tree
Reading state information… Done
Calculating upgrade… Done
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
raxial@Skynet ~ $ sudo apt-get dist-upgrade
Reading package lists… Done
Building dependency tree
Reading state information… Done
Calculating upgrade… Done
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
raxial@Skynet ~ $
“NO … I doubt if ANY flavour will have the 340 drivers in their repos yet.” ~ Fair 'nuff 
OK, run:
sudo gedit /etc/apt/sources.list.d/additional-repositories.list
and remove the line
from that file … so it’s empty.
SAVE the file and close gedit.
Now run the commands after the edit in my previous posting.
If the first “gedit” command errors … post what the error says … I’m not 100% sure if gedit is the text editor in Mint.
Right, it just got seriously busy upgrading stuff!
Entered the commands fine, and reboot. Then I got into Driver Manager, and - excitingly - I have a list to select from:
nvidia-331
Version 331.89-Oubuntu1~xedgers14.04.2
nvidia-340
Version 340.32-Oubuntu1~xedgers14.04.2
xserver-xorg-video-nouveau (currently selected)
Version 1:1.0.11+git20140904.3cd4c849-Oubuntu0sarvatt~trusty
It seems to want me to select one, then click Apply Changes?
Select the
nvidia-340
And apply it.
Once done and rebooted … post the output from:
sudo lshw -C display
and
dpkg -l | grep nvidia
Oh, wow. I think you’ve done it!
raxial@Skynet ~ $ sudo lshw -C display
[sudo] password for raxial:
*-display
description: VGA compatible controller
product: NVIDIA Corporation
vendor: NVIDIA Corporation
physical id: 0
bus info: pci@0000:01:00.0
version: a1
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress vga_controller bus_master cap_list rom
configuration: driver=nvidia latency=0
resources: irq:46 memory:f2000000-f2ffffff memory:e8000000-efffffff memory:f0000000-f1ffffff ioport:e000(size=128) memory:f3000000-f307ffff
raxial@Skynet ~ $ dpkg -l | grep nvidia
ii nvidia-340 340.32-0ubuntu1~xedgers14.04.2 amd64 NVIDIA binary driver - version 340.32
ii nvidia-340-uvm 340.32-0ubuntu1~xedgers14.04.2 amd64 NVIDIA Unified Memory kernel module
ii nvidia-opencl-icd-340 340.32-0ubuntu1~xedgers14.04.2 amd64 NVIDIA OpenCL ICD
ii nvidia-prime 0.6.2linuxmint1 amd64 Tools to enable NVIDIA’s Prime
ii nvidia-settings 343.13-0ubuntu1~xedgers14.04.1 amd64 Tool for configuring the NVIDIA graphics driver
Yup … that’s all looking fine
THANK YOU THANK YOU THANK YOU!! 
So much, Mark, for ALL your help. If I lived near you, I’d buy you a pint.
Heh … you’re most welcome, have fun in your shiny new Mint install
[EDIT]
Please remember to mark the topic (SOLVED)
You can do this by editing the FIRST posting in the topic, and changing
Subject: conflicting fb hw usage nouveaufb vs EFI VGA - removing generic driver (SOLVED)
TIA
Spot on … thanks
Sorry I missed all that, staff away day on Friday :-[
It’s possible to run with the Intel graphics in place, at least on a non-EFI machine (can’t see what difference EFI makes), as it’s what I’m running on my laptop. Although if this is a desktop, it’s a different ballgame as your monitor will probably be plugged into your nVidia card (why wouldn’t it?!)
Anyway, glad you got it sorted OP