Nintendo Switch Emulation: How to run Suyu on Steam Deck

If you want to play your Nintendo Switch ROMs on Valve's handheld, here is how to install Suyu on the Steam Deck.

With Yuzu's recent death, the emulation scene took a hit — but it was only a matter of time before a new Nintendo Switch emulator would appear and pick up where Yuzu left off. That's where Suyu comes in.

Well, recently, Suyu (which is based on Yuzu's source code), released a public beta, and after initial testing, it looks like it might be the go-to Nintendo Switch emulator for the time being.

So, if you want to play one of your legally acquired Nintendo Switch ROMs that you have dumped yourself on your Steam Deck — you know, for science — here is how to set up Suyu for the best compatibility on Steam Deck.

How to install Suyu on Steam Deck

First, we need to download Suyu. The Nintendo Switch emulator is currently in open beta, and you can find the matching files on their GitLab page. Here, you want to download under Other, the file called Linux (x86_64). Update: The GitLab page has been taken offline, you can find the downloads now under Suyu.dev.

Next, you want to install Suyu by simply double-clicking the downloaded .AppImage and next Execute. That should be enough to have Suyu installed.

How to install prod.keys, title.keys and the Nintendo Switch firmware

Unlike Yuzu, Suyu will not run if you don't use prod.keys, title.keys and the Nintendo Switch firmware. The only way I can tell you to get this, is by dumping them yourself from your jailbroken Nintendo Switch.

Start Suyu in the Steam Deck's desktop mode to install both keys and the Switch firmware.

As it's the first time you're starting the emulation tool, it will warn you about the missing files. Next, click on File in the top left corner, then to Open suyu folder, and here, open up the keys folder. This is where you want to drop both the prod.keys and title.keys files.

The Switch firmware needs to go in the Suyu folder in nand/system/Contents/registered. Drag all files (over 200) of the dumped firmware into this folder.

Alternatively, restart Suyu, then navigate to Tools and Install Firmware. Here select the folder with the dumped firmware files.

We're done now, Suyu is installed. To add Suyu to the Steam Deck's Game Mode, simply right-click the .AppImage and select Add to Steam. And with the SteamGridDB Decky Loader plugin, you can easily add your own artwork later.

How to optimize Suyu for Steam Deck

There are several modifications we can apply to the Steam Deck to make Suyu (and other Switch emulation) run better.

• First, we need to boot into the Steam Deck BIOS to change the VRAM. For this, turn off the Steam Deck completely. Hold the Power Button and the Volume Up Button. Release both as soon as you hear the chime. It can take a while before the BIOS appears. Here, click on Setup Utility. In the new window, go to Advanced, then set the UMA Frame buffer Size to 4G. Save and Exit!
• The Steam Deck will restart back to Gaming Mode. But for the next step, we need to boot into Desktop Mode. Click the Steam button, go down to Power, and then Switch to Desktop. Wait for the Deck to reboot.
• Next, we want to install CryoUtilities 2 by CryoBytes. Here is an in-depth explanation video by creator Kyle himself. But all it needs is to go to this link from your Steam Deck, and download the file called cryo_utilities. Double-click it and wait for it to install.
• When done, you will see the CryoUtilities app on your desktop. Double-click it, accept the disclaimer, then type in your sudo password. Next, click Recommended Settings. This will create a SWAP file of 16GB and change the Swappiness to 1.
• Still in Desktop mode, start up Suyu. Click on Emulation, then Configure. Under CPU, change the setting to Accurate, then go to Graphics > Advanced and here enable Force maximum clocks.
• If you haven't installed Decky Loader nor PowerTools yet, stay on Desktop Mode. Follow this guide to do so (skip to step 7 in that post). If you have both tools installed, we're done here. Go back to Gaming Mode.
• Back in gaming mode, open up Suyu. Next, click the menu button (that's the one on the right side with the three dots (•••)). Go down to Decky Loader (the icon with the plug), and look for PowerTools.
• We will change a few settings here — but these are only meant for Switch emulation. Disable them when you play games normally. First, disable SMT. Keep the Threads at 4. Then scroll down to the GPU section, and toggle the Frequency Limits. You now want to set both the Minimum and the Maximum to 1000hz. This gives you the closest Switch-like performance.

How to install DLCs and Updates on Suyu on Steam Deck

If you're unsure how to install your dumped DLCs and Updates for your Switch Games on Suyu, here's how:

• Boot into Desktop Mode. Click the Steam button, go down to Power, and then Switch to Desktop. Wait for the Deck to reboot.
• Open up Suyu. The process to install a DLC or an Update for games in your list here is the same. You have to click on File in the top, then Install Files to NAND... and navigate to the location of either your DLC or Update file. Select it, and wait for the process to stop. Repeat for the other files.
• This process will take a while, but you'll see if it succeeded if the Version Number below the Add-Ons tab changed.

That's it. You've now got the beta build of Suyu up and running and can now start to play your legally acquired and dumped Switch games on your Steam Deck.

In case you're wondering: TotK crashes for me, too, currently.