Let the distro make swap using default settings??

kosmo333,

That 2 x RAM yardstick for swap is pretty old and refers to the time when RAM was relatively small.

I have loads of RAM and invariably set swap at about 2GB.

my RAM is 4gb. The 25GB is enough for the MATE root partition (/)?

Probably, but personally I always err on the side of caution. I use 50GB for / on my laptop

kosmo333,

I have found 25GB is enough but you can make it larger if you wish (say 30GB to 50GB).

existing partitions are:
How can I preserve this Dell stuff?

How old is the laptop? Have you ever needed to use the dell utility from that partition? If not, why would you ever expect to need it? Are you aware that most tools like that can easily be downloaded from their web site?

With that said, keeping it seems unnecessary to me and needlessly complicates things.

Now to further answer your earlier questions about doing a UEFI install. Most installers will automatically do a uefi install if the disk has a GPT partition scheme, and will do a legacy install if it is MBR partitioned. Part of the UEFI install with automatic partitioning is creating an efi partition and flagging it as esp if not already done. The rest of the partitions vary by distro, but as has been said repeatedly, most will create swap, /, and /home for you with swap and / reasonably sized.

the laptop is 4 year old. I have never used this Dell utility. The installed system as purchased was Ubuntu 14.04 lts. Possibly, the Ubuntu onboard has been optimized for this machine. I'm worried not to get into the situation when some drivers are not available(graphics card, etc).

Does Ubuntu MATE 20.04 LTS installer have these features you mentioned?

kosmo333,

The Dell utility partition is a set of diagnostics.

I am not sure whether it also works in Linux as well as Windows, but in any event it takes up negligible space and does no harm. I would leave it alongside the recommended partitions for a UEFI boot in post #14.

This utility is on old disk. Since I'm going to install a new drive, how I can move it?

kosmo333,

I really would not bother with it.

There are tons of diagnostic tools available in Linux. Just install Ubuntu MATE 20.04.

beachboy2, some clarification about post #14, p.4,5 - making efi system partition with GParted is mainly for convenience?
As I read, when install on a new hard drive, during setup the MATE installer itself should create the EFI System Partition with correct filesystem type (fat32) and bootable flag, right?

You are right.
Using the installer and telling it to auto install will do that.
The disk must be GPT partitioned for that to work so you will still have to use gparted (or fdisk or gdisk or any other partitioning tool) and verify a GPT partition table has been written before you start the install. When you boot the install USB first go live with it and then you can use "sudo fdisk -l" easily for that purpose. It should be on that live USB. If you have to create a new GPT partition table I suggest you reboot so the install kernel sees that type partition table. If already there then start the install.

UPDATE:
I forgot to mention that in addition to GPT partitioning, efi uses a protected MBR. That means you have to do GPT + the protected MBR to force the installer to use UEFI for install. Some will still use MBR install without that protected MBR config.

kosmo333,

As computersavvy has stated, selecting Auto will create the efi system partition on a previously formatted GPT drive.

Personally I prefer to create partitions manually in order to have a separate Home partition because it makes life much simpler when upgrading or moving to another distro.

With Auto under Linux Mint on a GPT drive there will be an efi system partition and a root (system) partition.That is all.

Even Linux Mint's swap partition has now been replaced by a swap file:
https://forums.linuxmint.com/viewtopic.php?t=303359

beachboy2, yes that's what I wanted to clarify. As various guides usually mention that the Auto installer will make all correct partitions.But why should be used GPT, not MBR partitioning scheme for 500GB disk?