It is a long time since I tested anything on a spinning disk.
I have a 750GB Samsung 2.5" spinning disk and I have a a Acer Aspire with a dual-core Celeron N3350 and 4GB RAM.
If I can download, install and update the latest Xfce I am fairly certain your issue is hardware related somehow.
Maybe - the CPU vulnerability mitigations applied is having a huge effect on your system - I don’t know.
Until I have tested the above - I suggest you try to disable the mitigations by applying the following change to the grub default configuration
Using a terminal and a terminal editor e.g. micro, nano or vi - whatever you are familiar with - open the file
micro /etc/default/grub
Then locate the line reading
GRUB_CMDLINE_LINUX_DEFAULT="quiet udev.log_priority=3"
And amend it to read
GRUB_CMDLINE_LINUX_DEFAULT="mitigations=off quiet udev.log_priority=3"
Save the file and rebuild grub config
sudo grub-mkconfig -o /boot/grub/grub.cfg
Then reboot the system
reboot
Verify if this has any effect.
From the inxi above I very much looks like you are using BIOS/MBR - I don’t see an EFI partition - is that correct?
I have know installed Xfce rel.21.1.6 minimal on the mentioned system using a spinning disk.
It is noticable slow - as I expected but not unusable - it takes approx. 2-3 minutes to boot to a desktop with wallpaper and shortcuts.
The initial update was 4-5s using the terminal - (sudo pacman -Syu) and installing the linux515 kernel took a 3-4 of minutes including download and rebuilding the initrd.
My test system is more recent EFI based system - the inxi output can be read from
$ inxi --admin --verbosity=7 --filter --no-host --width | curl -F 'f:1=<-' ix.io
http://ix.io/3DY2
$ inxi --admin --verbosity=7 --filter --no-host --width | curl -F 'f:1=<-' ix.io
http://ix.io/3DY5
$ systemd-analyze | curl -F 'f:1=<-' ix.io
http://ix.io/3DY6
$systemd-analyse blame | curl -F 'f:1=<-' ix.io
http://ix.io/3DY7
My test system
Machine:
Type: Laptop System: Acer product: Aspire ES1-432 v: V1.08 serial: <filter>
Chassis: type: 10 serial: <filter>
Mobo: Acer model: Maia_AP v: V1.08 serial: <filter> UEFI: Insyde v: 1.08
date: 10/21/2016
CPU:
Info: Dual Core model: Intel Celeron N3350 bits: 64 type: MCP arch: Goldmont
family: 6 model-id: 5C (92) stepping: 9 microcode: 44 cache: L2: 1024 KiB
bogomips: 4378
Speed: 796 MHz min/max: 800/2400 MHz Core speeds (MHz): 1: 796 2: 2064
Although not as old as yours - Manjaro is still usable - and your system still appears to have a faster CPU with hyperthreading.
Still leaves me to wonder what could cause your experience.
The logfile shows your sata controller renegotiating - for ever - so you are having a hardware problem with the board or the disk.
I suggest you try switching the sata port - preferably to another controller - and to try with another disk.
The interesting part is Intel® H55 Chipset I have an old system based on either the same chipset or very similar.
This system was a pain to get installed with Manjaro - I don’t recall all the details - and can’t check as it has been decommissioned - still standang next to my desk - partly ripped.
I recall the firmware was flaky and EFI dysfunctional - so to get it working I booted in EFI mode and installed in BIOS/MBR mode.
The ISO grub menu was very slow to respond and it required a lot of patience - that I do recall. This was not a fault or flaw with Manjaro. I eventually got it working and it served some time as a build system for Manjaro ISO.