Note that I am about four months into Linux, so I might very well make some completely untrue claims here. This is intended to serve as a documentation of how I got things working and to explain some of the concepts I had a hard time grasping to begin with. I am a long-time Windows user so I am trying to keep the new Linux migrant in mind here.

CachyOS is Arch-based which is famously a bit obnoxious - a little bit like Houdini vs something like Blender, not wanting to assume a lot of things for you, but leaving you in control. My experience with Cachy so far has not been obnoxious at all, and they seem to give you most of what you need to avoid the command line in the early days.
I was on Fedora before which caused me way more trouble from SELinux, so I am quite happy that this has all been much simpler so far.

Downloading the ISO and preparing the boot media

1. Download CachyOS
2. Click Download Desktop Edition -> Direct
3. I also downloaded the Checksum and Signature

Side quest while downloading

While downloading, I ended up on a side quest reading about file systems, when I reached the bottom of the page saying:

TL;DR
Use the default filesystem BTRFS as it is considered stable and has a lot of neat features (snapshots, compression, etc). Use XFS or EXT4 for a simple and fast filesystem.

I also read about boot managers, where I had heard a bit of good things about GRUB before so I was inclined to go with that one. The TL;DR agreed with me.

Because my only experience with Linux so far is Fedora on KDE Plasma and Rocky on GNOME, I will choose KDE Plasma as my Desktop Environment

Verifying the ISO

Checking the downloaded files
I put the three downloaded files into a folder together and right-clicked to Open Terminal Here which just brings up a bash console set to /home/dannylaursen/Downloads/cachyos.

1. I use caton the .sha256 file to read the contents. You can also open it in Notepad or something.
2. I run sha256sumon the .iso
3. The contents of the .sha256 file and the output of the step two command should be a match
   Sha256sum works in a way that small differences in the files will result in a clear difference in the two, so it should be clear just skimming over the two keys if they are the same or not.
   See my example terminal below:

dannylaursen@fedora:~/Downloads/cachyos$ cat cachyos-desktop-linux-260124.iso.sha256  
0c070fba1eb06a740983e8e195ecb686c4fc2060920137af1cedbd5ffca5be47  cachyos-desktop-linux-260124.iso  
dannylaursen@fedora:~/Downloads/cachyos$ sha256sum cachyos-desktop-linux-260124.iso    
0c070fba1eb06a740983e8e195ecb686c4fc2060920137af1cedbd5ffca5be47 cachyos-desktop-linux-260124.iso

Below I check the gpg signature. I just followed the documentation one to one here

dannylaursen@fedora:~/Downloads/cachyos$ gpg --keyserver hkps://keys.openpgp.org --recv-key F3B607488DB35A47  
gpg: key F3B607488DB35A47: "CachyOS <admin@cachyos.org>" not changed  
gpg: Total number processed: 1  
gpg:              unchanged: 1  
dannylaursen@fedora:~/Downloads/cachyos$ gpg --verify cachyos-desktop-linux-260124.iso.sig cachyos-desktop-linux-260124.iso  
gpg: Signature made 2026-01-24T16:16:37 CET  
gpg:                using RSA key 882DCFE48E2051D48E2562ABF3B607488DB35A47  
gpg: Good signature from "CachyOS <admin@cachyos.org>" [unknown]  
gpg: WARNING: This key is not certified with a trusted signature!  
gpg:          There is no indication that the signature belongs to the owner.  
Primary key fingerprint: 882D CFE4 8E20 51D4 8E25  62AB F3B6 0748 8DB3 5A47  

Note that the important line here is Good signature from "CachyOS..." No need to worry about this warning.

Prerequisites

Open up the UEFI / BIOS

Open up your BIOS. Most machines have a screen during startup that show the logo of the motherboard or the brand. Could be ASUS, ACER, HP, etc., and below they wills say something like "press F2 to enter BIOS". Just spam that key until you see the UEFI. In mine, on an ASUS motherboard, I need to go to my boot options to set the following two settings:

1. Secure boot must be turned off
2. CSM must be disabled

Flash the Boot Media

Now that the iso is downloaded and I have made some decisions, it is time to flash the boot media. I have a 64 GB USB thumb drive lying around so I will simply put it into my machine. I will use the Fedora Media Writer to flash the ISO onto the USB drive. This part takes roughly 10 minutes (probably depending on speeds of the different drives working). Fedora Media Writer also works on Windows.

Installation

This section more or less follows the Desktop Edition installation guide, but I've added some extra context here and there.
We are installing with GRUB as our boot manager so I will follow the steps for GRUB under UEFI/GPT

1. Boot from USB drive

Insert the flash drive in one of your USB ports and boot to the UEFI / BIOS (or your boot menu if they are different things on your motherboard.

The boot menu usually appears by doing something like spamming esc or F12 on startup). The name of your USB drive will appear as one of the possible drives to boot from.

Let's say your drive is calledKingstonData_64GB, and it appears mutliple times, but prefaced with UEFI or BIOS, select the one that only has the "clean" name.

Hit enter to start the boot.

2. Live image

I was preparing lunch while doing this so when I had reached the Boot Menu and selected to boot from my USB drive, I left for a minute and came back to the computer having launched CachyOS.
Most Linux distros come with a live test version of the OS directly on the installation media so you can check that your WIFI, bluetooth, usb ports, etc. all work as you expect they would.

If you are still on the fence, we have spent about 45 minutes now so if you spend the next 15 minutes poking around to see if you like the feeling of the OS, you will have invested 1 hour of your time into learning some new things and trying something out.
If it is not for you, now is the time to turn back and not go any further. If you are still unsure, you can follow the documentation to dual boot.

3. Walking through the installer

We are presented with a nice welcome message with some useful links along with a Launch installer button. Click that. The installer autodetected my language to Danish, but I think that will make it confusing to follow the install guide, so I will change it to British English.

Set your time zone and location

Set your preferred keyboard layout.

Select GRUB as the Bootloader

Under Partitions, I choose my 500GB NVME storage device and set it to Erase disk

Under Dekstop, I chose Plasma (KDE Plasma). This one feels familiar coming from Windows but is really easy to customize to your own liking.

I dislike Firefox implementing AI features, so I will turn off Firefox and language packages under Packages

Under Users, I set up my user and a computer name that I like along with a good password. From Fedora, I know that you should ideally have a user that CAN gain admin rights, but have the root user disabled just to add an extra layer of security. However, I am not sure how or why that works, so I will leave "Use the same password for the administrator account" on.

You can read the Summary if you want, but assuming you entered what you wanted, now it's time to Install.

The Cachy installer tells you some "fun facts" about its performance and security. I don't really know what most of it is, but it feels like a video game loading screen.

The install took about 10 minutes and is now ready to restart
Enable Restart now and click Done. The screen now shows a bunch of text and restarts.

This is where, not having the prerequisites in order caused problems for me. I went back and disabled CSM and secure boot, started over, doing exactly the same things, and it worked perfectly.

Linux things

Errors when booting?

When booting up, you might first see a few errors. For me, it used to show No irq handler for vector... for a few seconds. This turned out to be because my motherboard firmware hasn't been updated, ever. My laptop shows a different error. From what I've seen online and experienced myself, these errors don't really matter, but you could always try to look them up to see what other people say.

Boot Manager

When you start up your computer, you will now see the Boot Manager. We chose GRUB because it is old and stable and supports snapshots which can help you recover your system. Think of it like save files in a video game. It displays for 5 seconds by default, and gives you the option to boot from a snapshot instead of going straight into Cachy. You can hide this menu by modifying a text file on disk.

What about the "Windows" key?

The Windows key is now your "Meta" key. Just like on Windows, you can hit the Meta key to open up your, now much more useful, start menu and immediately search for soemthing.

Post installation

Cachy have their own recommendations post installation. Here is what I noted:

Welcome screen and package manager

The welcome screen shows all the same things as on the live media except now we have Apps/Tweaks and Install Apps. Apps/Tweaks opens a speed-dial type menu with some quick buttons for configuration. I didn't use any of these yet.
Install Apps opens the CachyOS Package Installer which is basically an app store for CachyOS. If an app exists in the package installer, install it through the package installer. It is easy, it is safe, and it keeps track of updates all by itself.

Arrange dual monitors

The first thing I will do, is set up my dual monitors correctly. Just like on Windows, right-click the Desktop -> Display Configuration, click Edit Arrangement and move them around. Easy and intuitive.

Install NVIDIA Drivers

1. Check this table to find out which drivers your card needs. This is like on Windows, different cards use different drivers. Mine is a 3070 in the "Maxwell" family, so I need nvidia-580xx-dkms
2. Open the CachyOS Package Installer go to the Repo tab
3. Search for nvidia-580 and select a total of 4 packages:
   1. nvidia-580xx-open-dkms
   2. nvidia-580xx-settings
   3. nvidia-580xx-utils
   4. opencl-nvidia-580xx
4. Hit Install
   If you are on one of the newer cards needing the nvidia-open drivers according to the table, the packages will be called nvidia-open-dkms, nvidia-settings, nvidia-utils, and opencl-nvidia. If your card is older, substitute 580xx for whichever version is appropriate for you.

Other packages

I also installed OBS and Blender through the Package Installer.
I mentioned disliking Firefox, so I installed LibreWolf instead. AI free Firefox that comes with uBlock Origin by default.

Install system updates with Octopi

https://wiki.cachyos.org/configuration/post_install_setup/#updating-the-system
Looks a little techy, but you just have to press Check Updates and System Upgrade and the Output console will show you if any packages need updating.

Installing Houdini

If you have installed your NVIDIA drivers, you are ready to install Houdini.

1. Download Houdini Launcher
2. Right-click the install_houdini_launcher.sh file, go Properties -> Permissions, and enable Allow executing file as program. Hit OK
3. Right-click the file again, and hit **Run in Konsole
4. You might be prompted for your password, and to hit Y then enter to confirm that you wish to install the launcher
   It will tell you to go to /opt/sidefx/launcher/bin and run ./houdini_launcher, but you can just open it like any other app, hit the Meta key, search Houdini, open the launcher.
   Now everything should work exactly the same as on Windows.

Congrats, you are now both a massive Houdini nerd and an "Arch btw" nerd.

Automounting Additional Drives

Check this guide for screenshots.
Houdini artists need space for their caches and you don't want to type your password four times when you sign in.

In Dolphin (which is your File Explorer in KDE Plasma), you can see a list of Devices, which are most likely called something like sda1, sdb1, nvme0n1, etc.
sd is a sata disk (a spinning hard disk or sata SSD)
nvme is kind of self-explanatory - it is an nvme SSD.

If you try to access one of them, you will be asked for your password to mount it. This is good if you're trying to hide some files, but less good if you want to store your FLIP caches on your 4TB hdd.

1. Open KDE Partition Manager
2. Select one of your devices. In my case, I have a Samsung SSD 750 EVO-500GB
3. You will see the partition table for the device. When I initially came from Windows, I had many small 100MB partitions, which are probably used by Windows for some recovery stuff. You can right-click and delete those if needed
4. Right-click the partition you want to automount, and click Edit Mount Point
5. Set Identify by to UUID
6. Set the path to something like /media/SSD01 (/media is the "proper" place to mount drives, and SSD01 seemed like a fitting name)
7. Enable Do not prevent the system from booting if not mountable
8. Enable Users can mount and unmount
9. Any other options should be disabled
10. Hit OK
11. If you deleted or changed any partitions, be sure to hit Apply