First of all, let me thanks to @Terrance the information he gave me on the previous comment.
The process of installation succeeded and the graphics display works perfectly (so far)!
However, I'm not sure if the driver was really installed, because there were some errors during the process. My intent here is to make a report of the PROCESS I made.
I must say, however, that the process I shall describe assumed all the possible risks, including the loss of data, the damage of the System and a possible full install of Kubuntu 18.04.
For those who want to try this, I strongly recommend a backup of its personal data!
STEP 1
It is always wise to read the information available before an attempt to do anything.
At this link (https://www.nvidia.com/Download/driverResults.aspx/71303/en-us ), the tab "Additional information" has some important information which is necessary to understand part of the installation process.
I strongly recommend README (http://us.download.nvidia.com/XFree86/Linux-x86_64/173.14.39/README/README.txt )
On "Chapter 2. Minimum Software Requirement" there are some software elements which must be verified/matched on Kubuntu 18.04:
linux kernel version: do a compare with supported versions:
sudo cat /proc/version
So far, there is no problem, as Kubuntu 18.04 kernel version is 4.15.0.
X.Org: do a compare with supported versions:
sudo Xorg -version
Here there is an issue. According to the driver supported versions, the last one declared is 1.15. Kubuntu 18.04 xorg version is 1.19.6, which is more recent and apparently don't comply with the versions for which the driver was made. However is said that "Sometimes very recent versions are not supported immediately following release, but we aim to support all new versions as soon as possible."
STEP 2
Place 'NVIDIA-Linux-x86_64-173.14.39-pkg2.run' on /Home/User folder, for commodity.
STEP 3
Enable Kubuntu 18.04 to start in shell mode.
sudo systemctl set-default multi-user.target
(...)
sudo reboot
Disable (blacklist) nouveau (see info here).
sudo bash -c "echo blacklist nouveau > /etc/modprobe.d/blacklist-nvidia-nouveau.conf"
sudo bash -c "echo options nouveau modeset=0 >> /etc/modprobe.d/blacklist-nvidia-nouveau.conf"
cat /etc/modprobe.d/blacklist-nvidia-nouveau.conf
(...)
sudo reboot
STEP 4
Build the NVIDIA kernel module (I wonder if this was really necessary, as the compilation failed):
sudo apt install binutils
(...)
sudo apt install gcc
(...)
sudo apt install make
(...)
sudo apt install dkms #Contribution by @Terrance
(...)
sudo reboot
STEP 5
(The moment of truth...) Autocompile and install 'NVIDIA-Linux-x86_64-173.14.39-pkg2.run'.
sudo sh NVIDIA-Linux-x86_64-173.14.39-pkg2.run
(...)
Building kernel module error
#Compilation didn't succeed - WTF!!!!
At this moment I gave up! I was prepared to a clean install of Kubuntu 18.04.
STEP 6
Replace the GUI interface:
sudo systemctl set-default graphical.target
(...)
sudo reboot
STEP 7
Funny thing!
The system booted with a perfect GUI which I've never seen!
After several tests, everything was working perfectly and with no lags.
In conclusion, what were the processes I left with no recovery?
the Xorg and the nouveau, I think.
CONCLUSION
I'm not a technician, and frankly I don't really care what happened in technical terms that lead to put my NVIDIA Quadro FX 1300 back to work on Kubuntu 18.04.
Maybe some technicians can answer to those questions in detail. Is up to them.
The fact is that that old graphics card is working and for me it's great!
Probably this process may function on any nvidia-173 GPU. However, that testings will be for someone who wants to give a try using this process.
I hope, however, that the system be stable enough after a new Kubuntu upgrade.
Cheers.
