How to get the best quality and performance from Oculus Quest and Quest 2 VR headsets via Oculus Link wired connection.
The Oculus Link wired connection for the Oculus Quest and Quest 2 VR headsets is now out of beta, but it still requires proper setup and some tweaking to get the best quality and performance.
Be sure to use USB 3.0.
Oculus Link will work with USB 2.0, but only at 72Hz refresh rate, and trying to increase the bitrate will result in stuttering. In addition, USB 2.0 has a higher latency.
USB 3.0 unlocks 80Hz and 90Hz modes for the Quest 2 and allows higher bitrates to reduce compression artifacts. How well USB 3.0 mode will work depends on your motherboard and specific cable.
Facebook is selling the official 5m cable for $79. This fiber optic cord is thin and light, but you can find much cheaper third party alternatives on sites like AliExpress.
To make sure you’re in USB 3.0 mode, open the Devices tab in the Oculus PC app and select your headset. You should see a green check mark.
If the connection appears as USB 2.0, try other USB 3.0 ports on your PC. Also try restarting your computer and VR headset. If your video card has a USB-C port, use it. If none of these methods work, you can try purchasing and installing a PCI-E USB card.
The latest graphics cards from NVIDIA perform better.
For general PC gaming, the choice between NVIDIA and AMD usually comes down to pure performance versus price. For stock VR headsets for PCs that use DisplayPort or HDMI, this comparison is usually also relevant.
But when using Oculus Link, the graphics card doesn’t just send raw frames. Since USB bandwidth is much less, the video stream is further compressed by the GPU’s video encoder.
In 2018, NVIDIA introduced a much improved video encoder in their Turing RTX 2000 series graphics cards. The encoder in the recently released RTX 3000 Ampere cards is almost identical to it.
But video encoders on old NVIDIA cards and new AMD cards, for example, the RX 5000 series, have noticeably worse image quality, as well as a large delay. We haven’t done any video encoder evaluations in the recently released AMD RX 6000 series yet.
Remember to use the latest video card drivers.
90Hz is great, but can be difficult to achieve.
Oculus Link runs at 72Hz by default. In USB 3.0 mode, the Quest has the option to increase the frequency to 80Hz or 90Hz.
A higher refresh rate reduces latency, makes controller tracking smoother, makes the virtual world feel more cohesive, reduces eye strain, and can even reduce motion sickness in VR. But 90 Hz is 25% more load for a PC.
If a particular game is stuttering even at lower graphics settings, try lowering the refresh rate, but otherwise we recommend setting it to 90Hz wherever possible.
How to improve visual effects.
There are two separate settings that primarily affect the visual quality of Link: render resolution and encoding bitrate.
The render resolution is, as you would expect, the resolution at which the PC renders the video. The limitation may be the processor, video card, RAM and other performance-related characteristics.
You can set it in the same panel as Refresh Rate in the Oculus PC app. Select Quest 2 and go to the Devices tab to find the settings. Facebook recommends leaving it automatic.
Because Link compresses the image for transmission via USB, the image quality is also affected by the bitrate of that video stream.
You can manually set this bitrate using the Oculus Debug Tool (ODT) – located in the oculus-diagnostics subfolder in the Support folder of the Oculus software directory. Full default path C:\Program Files\Oculus\Support\oculus-diagnostics.
Setting ODT values to 0 means the default value. Although the program does not show it in any way.
Encoding resolution width used to be the third main visual quality setting for a link, but as of version 23 it is now set automatically based on the rendering resolution, so leave it at 0 (default).
It is unclear what the default bitrate is now. Back in May, consulting CTO John Carmack said it was “about 150 Mbps”.
Increasing the bitrate improves image quality and reduces compression artifacts. But it also increases latency and can cause stuttering if the graphics card or headset is underpowered.
Facebook engineers say that after 250 Mbps it’s hard to see the improvement in image quality, but our team is especially sensitive to this compression and we see a difference up to about 350 Mbps. The maximum speed is 500 Mbps, but it is not recommended to exceed 250 Mbps. In the future, Facebook plans to automatically set the encoding bitrate.