glc78's questions

Looking for information about total memory on my laptop, I've found the following but I have some doubt about the meaning.

From the dmidecode command I obtain:

Handle 0x0010, DMI type 16, 23 bytes
Physical Memory Array
    Location: System Board Or Motherboard
    Use: System Memory
    Error Correction Type: None
    Maximum Capacity: 8 GB
    Error Information Handle: Not Provided
    Number Of Devices: 2

Handle 0x0011, DMI type 17, 34 bytes
Memory Device
    Array Handle: 0x0010
    Error Information Handle: Not Provided
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 4096 MB
    Form Factor: SODIMM
    Set: None
    Locator: Bottom
    Bank Locator: CHANNEL A
    Type: DDR3
    Type Detail: Synchronous Unbuffered (Unregistered)
    Speed: 800 MHz
    Manufacturer: Kingston
    Serial Number: 5A396D76
    Asset Tag: Asset Tag: 
    Part Number: KHX1600C9S3L/4G   
    Rank: 1
    Configured Clock Speed: 800 MHz

Handle 0x0013, DMI type 20, 35 bytes
Memory Device Mapped Address
    Starting Address: 0x00000000000
    Ending Address: 0x000FFFFFFFF
    Range Size: 4 GB
    Physical Device Handle: 0x0011
    Memory Array Mapped Address Handle: 0x0016
    Partition Row Position: 1

Handle 0x0014, DMI type 17, 34 bytes
Memory Device
    Array Handle: 0x0010
    Error Information Handle: Not Provided
    Total Width: Unknown
    Data Width: Unknown
    Size: No Module Installed
    Form Factor: SODIMM
    Set: None
    Locator: Top
    Bank Locator: CHANNEL A
    Type: Unknown
    Type Detail: Unknown
    Speed: Unknown
    Manufacturer: Empty
    Serial Number: Empty
    Asset Tag: Asset Tag: 
    Part Number: Empty
    Rank: Unknown
    Configured Clock Speed: Unknown

Handle 0x0016, DMI type 19, 31 bytes
Memory Array Mapped Address
    Starting Address: 0x00000000000
    Ending Address: 0x000FFFFFFFF
    Range Size: 4 GB
    Physical Array Handle: 0x0010
    Partition Width: 255

I was thinking my HP 15g-207nl supported at max 4GB of memory, but there I see an 8GB as for the maximum capacity. Which is the truth? Then again, the file /proc/meminfo tells me this:

MemTotal:        3467664 kB
MemFree:          493996 kB
MemAvailable:    1093044 kB
Buffers:           72928 kB
Cached:           754636 kB
SwapCached:         1460 kB
Active:          1726432 kB
Inactive:         871336 kB
Active(anon):    1346256 kB
Inactive(anon):   519488 kB
Active(file):     380176 kB
Inactive(file):   351848 kB
Unevictable:          32 kB
Mlocked:              32 kB
SwapTotal:       3613692 kB
SwapFree:        3588868 kB
Dirty:               456 kB
Writeback:            40 kB
AnonPages:       1769496 kB
Mapped:           404592 kB
Shmem:             95540 kB
Slab:             178208 kB
SReclaimable:     135680 kB
SUnreclaim:        42528 kB
KernelStack:       11408 kB
PageTables:        39620 kB

I think the pc has a 4GB memory card mounted, but neither with Gibibyte or Gigabyte unit system I'm able to sum up and find those 4GB here. Where are they? And what do MemTotal, MemFree and MemAvailable precisely represent?

I created the following alias to run pip3.7 everytime I use pip command:

pip='pip3.7'

Now, bash says:

pip -V pip 18.1 from /home/uname/.local/lib/python3.7/site-packages/pip (python 3.7)

but, the command which pip says:

which pip /home/uname/.local/bin/pip

while the executables for pip3.7 seem to be located at different folders:

whereis pip3.7: /usr/local/bin/pip3.7 /home/uname/.local/bin/pip3.7 /home/uname/.local/bin/pip3

I think maybe that in which pip, the world pip is not seen as the command actually triggered by the alias, thus it returns the pip path like if alias would not exist. This confuses me on which version actually runs with pip command.

Grub has disappeared.

A few days ago, I removed Python 3 and that screwed up the whole Ubuntu graphical interface. I fixed this by reinstalling Ubuntu-desktop.

However, the Grub menu does not show up at the machine boot any more, and the PC directly loads Windows.

The following are two screenshots of the current BIOS set-up configuration. It seems to be as it was, but I could be wrong:

If, in the boot manager, I chose Ubuntu, the classic purple Grub screen appears and allows me to choose the OS I prefer.

How can I make the Grub show up first again?

My Ubuntu 16.04 LTS seems stuck and has lost its graphical interface after the removal of python3. I thought only python2 was crucial for the System. However: how to fix this mess? System does not answer to any command, I can only create a new document in a completely empty desktop. Trying to save it I see that my folders still exist. Combination ctrl+alt+t does not open terminal.
I tried with sudo apt-get install --reinstall ubuntu-desktop in the shell available during the recovery mode. It asks me to install 120MB of packages, but fails in fetching several of them. So it does nothing. Any help?

I've just now installed Python 3.7 and I'd like to understand why I get the following output from bash:

g-luca@hp-notebook:~$ python3.7 -V
Python 3.7.0
g-luca@hp-notebook:~$ python3 -V
Python 3.5.2
g-luca@hp-notebook:~$ python -V
Python 2.7.12

I created the file ~/.bash_aliases within these lines:

# my alias here

eclipse="eclipse</dev/null &>/dev/null &"
okular="okular</dev/null &>/dev/null &"
libre="libreoffice</dev/null &>/dev/null &"

My ~/.bashrc is ready to find aliases:

if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases
fi

I then executed . ~/.basharc and also source .bashrc but aliases I created still don't work.

Where can I find a list/file of all aliases created in Ubuntu 17.04? I mean shortcuts for commands most frequently used and more.

I'm trying to fix a date&time problem in my Ubuntu 17.04 but I cant't find mentioned file /etc/default/rcS. I find only this path /etc/rcS.d but I think it has nothing to do with UTC default setting. I'm looking for option UTC=yes/no.

if I want to connect to POSTGRESQL db with a Linux user that I've created, let's say "Joe", should I locate pgadmin folder within python environment under Joe's folder?