When block noise occurs, the screen becomes coarse, ruining the beautiful video. If viewers say “The quality is poor” or “It’s hard to watch and laggy,” motivation might decrease.

However, block noise can be prevented by optimizing the settings of OBS.

This article thoroughly explains the causes and solutions for block noise in OBS. From bitrate differences to encoder variations and the impact of the internet connection, everything will be clearly explained.

If you’re struggling with block noise in OBS, let’s review your settings immediately to achieve high-quality video.

What is block noise in OBS?

Block noise refers to issues like the image becoming “distorted,” “blurry,” “poor,” or “coarse.”

In OBS, instead of recording or transmitting video data as is, it outputs the video while encoding (compressing) it.

Since the video data is too large as is, the bitrate is adjusted to reduce the data size. However, in the compression process, minute details of the video are trimmed, leading to the occurrence of block noise.

In scenes like the following, block noise becomes particularly noticeable.

• Videos with intense movements (such as FPS or sports games)
• Dark scenes or videos with many gradients (nightscapes or scenes with lots of shadows)
• Situations where encoding cannot keep up (low-spec PCs or inappropriate settings)

To prevent poor image quality, it’s necessary to adjust OBS’s encoding settings, tweak the bitrate, and review the connection environment.

Causes and solutions for block noise occurrence in OBS

To aim for removal or reduction of block noise in OBS, understanding its main causes is crucial.

Broadly, the possible causes can be divided into the following three:

• Bitrate
• Encoder
• Network speed

When the bitrate is inappropriate or when encoding can’t keep up, parts of the video are trimmed and appear as noise. From here, each cause and its solution will be explained.

Bitrate is not optimal

Bitrate refers to the amount of data that can be transmitted per second. Too low, and the video is overly compressed, making noise more likely, and too high, there’s a possibility that it might be forcibly recompressed by the platform, leading to degraded quality.

For example, block noise on platforms like YouTube or Twitch originates from the re-encoding process on their sides.

Even if you aim for high quality by excessively increasing the bitrate, it might get caught in limitations and be recompressed, meaning quality doesn’t improve.

Conversely, if streaming continues below the recommended bitrate benchmark, the video will likely become riddled with noise.

Below is a summary of recommended bitrate settings according to resolution.

Resolution	FPS	Recommended Bitrate (Twitch)	Recommended Bitrate (YouTube)
720p	30	2,500–4,000kbps	1,500–4,000kbps
720p	60	3,500–5,000kbps	2,250–6,000kbps
1,080p	30	4,500–6,000kbps	3,000–6,000kbps
1,080p	60	6,000–9,000kbps	4,500–9,000kbps

While being aware of platform-specific upper limits and recommendations such as those for Twitch and YouTube, also consider your own connection speed in your settings.

The method to set bitrate in OBS is explained in detail in the following article.

>>Optimal OBS Bitrate Settings for Streaming and Recording Explained

Encoding cannot keep up

An encoder is a system that compresses video to reduce the data size.

In OBS, mainly two types of encoders can be used.

Encoder	Features
x264 (Software Encoding)	Encodes using CPU. High quality but high CPU load.
NVENC (NVIDIA GPU Encoding)	Encodes using NVIDIA GPU. Low load and stable, but inferior quality with older GPUs.

OBS performs encoding in real-time while executing streaming and recording. If encoding cannot keep up, parts of the video may be missing, causing block noise.

If the settings don’t match the machine specs, encoding delays can lead to corrupted video.

How to change encoders in OBS is explained in detail in the following article.

>>OBS Encoder Settings Guide: Optimize Streaming and Recording Quality

This section explains causes and remedies for block noise depending on the encoder type.

x264 (Software Encoding)

x264 uses software encoding via the CPU, allowing fine-quality adjustments but tending to increase CPU load.

Encoding requires significant computation, so if the CPU is heavily used by other apps (like games) during streaming, encoding can’t keep up, leading to block noise.

If you set the preset (processing speed) to “slow,” high-quality video can be theoretically achieved, but CPU load might soar, leading to potential real-time encoding delays.

Conversely, setting to “veryfast” or “superfast” reduces load but compromises quality.

By making adjustments like the ones below, it’s possible to harness x264’s strengths while reducing block noise:

• Continuously check CPU usage, and if the load is too high, lower presets, bitrate, or resolution
• On high-performance machines with CPU room, try slightly heavier presets
• Minimize simultaneous use with other apps to allocate resources to OBS encoding

NVENC (NVIDIA GPU Encoding)

NVENC is an encoding method using dedicated hardware in NVIDIA’s GPU.

Reducing CPU load is a notable advantage, but depending on the GPU generation or settings used, block noise might feel noticeable as “poor quality.”

The older GTX series NVENC exhibits slightly inferior quality, with noise more prominent in fast-moving scenes.

On the other hand, new-generation NVENC, used from the RTX series, improves encoding quality, and by choosing “New NVENC” on the OBS side, stable quality is easier to achieve.

Here are three effective measures:

• Utilize new-generation NVENC post-RTX as much as possible
• Turn on “Psycho Visual Tuning” and secure an optimal bitrate
• Lower game graphics settings moderately for GPU resource flexibility

Low network speed

In streaming, not just a PC’s processing power but also the upload network speed is crucial.

If network speed is inadequate, streaming video data in real-time is difficult, leading ultimately to frequent block noise or image distortions.

Moreover, on unstable connections, packet loss can easily occur, causing parts of the video to be missing, serving as a further cause of noise.

The following table summarizes the estimated upload speeds by resolution and FPS, so check your network specs by them.

Resolution	FPS	Recommended Upload Speed
720p	30	3Mbps or more
720p	60	4.5Mbps or more
1,080p	30	6Mbps or more
1,080p	60	8Mbps or more

If you have concerns about network speed, consider setting the bitrate modestly or switching from Wi-Fi to a wired connection to reduce block noise.

Differences in block noise from OBS settings [Comparing actual videos]

Even with the same video source, block noise appearance can dramatically change depending on how you choose your OBS settings, bitrate, and encoder.

From here, let’s see comparison examples of how bitrate quality differences and encoder choices affect video.

Image quality comparison by bitrate

If the bitrate is too low, the video becomes overly compressed, making block noise noticeable during scenes with motion.

Conversely, securing a good bitrate allows for less noise, even during intense motion, maintaining smooth video.

The table below compares how the quality changes when only the bitrate is changed for the same video.

Bitrate	Features	Quality Evaluation
2,000kbps	Low bitrate. Block noise is noticeable during intense motion	★☆☆☆☆
4,500kbps	Standard quality, with slight blurring of details	★★☆☆☆
6,000kbps	Twitch recommended ceiling. Relatively clear even with intense games	★★★★☆
9,000kbps	YouTube for high quality. Nearly no noise	★★★★★

Quality comparison by encoder

OBS mainly has two types, x264 (CPU encoding) and NVENC (GPU encoding), and with the same bitrate, there’s a difference in the finished video.

For example, x264’s “veryfast” keeps CPU load low, but block noise is noticeable due to fast processing.

However, if set to “medium” or “slow,” image quality improves, but sudden CPU load rise can occur, making encoding unable to keep up.

The table below compares their characteristics and quality differences.

Encoder	Features	Quality Evaluation
x264 (medium)	Improved quality, but higher CPU load	★★★★★
x264 (veryfast)	Low CPU load, but detail loss is likely	★★★★☆

[Block noise countermeasures] Introducing optimal OBS settings for different streaming environments

To suppress block noise and deliver comfortable video to viewers, it is essential to set OBS tailored to PC specs, network status, and streaming platforms.

Next, recommended settings by skill level, categorized into beginners, intermediates, and advanced users are presented. Check which settings suit your environment for smooth streaming.

Beginner level | Simple and stable settings

Beginners unfamiliar with OBS operations should start with “720p, 30fps,” as it tends to be more stable.

▼Recommended settings for beginners

Setting Item	Recommended Setting
Encoder	NVENC (NVIDIA GPU-equipped PCs) or x264 (CPU)
Resolution	720p (Base resolution: 1,280×720)
FPS	30fps (sufficient for less dynamic streaming)
Bitrate	3,500–4,500kbps
Scaling Filter	Bilinear or Lanczos

▼Setting points

• By keeping the bitrate low, it becomes stable even with slower network speeds
• If using x264 (CPU encoding), select the “veryfast” preset (to reduce CPU load)
• If NVENC is usable, high-quality streaming is possible while reducing GPU load

Intermediate level | Balancing quality and stability

If there’s room for PC performance and network speed, set the resolution to 1,080p and FPS to 60fps for smooth and clear video.

▼Recommended settings for intermediates

Setting Item	Recommended Setting
Encoder	NVENC (Recommended: RTX series)
Resolution	1,080p (Base resolution: 1,920×1,080)
FPS	60fps (for games with lots of movement)
Bitrate	6,000kbps (Twitch max) or 9,000kbps (YouTube recommended)
Keyframe Interval	2 seconds (Platform recommended value)
Preset (x264)	“fast” or “medium” (maintains high quality)
Scaling Filter	Lanczos

Advanced level | Balancing high quality and high performance

With a high-performance PC, you can fully utilize OBS settings for maximum quality streaming.

▼Recommended settings for advanced users

Setting Item	Recommended Setting
Encoder	NVENC (latest) or x264 (slow)
Resolution	1,440p (Base resolution: 2,560×1,440)
FPS	60fps (for games with lots of movement)
Bitrate	12,000–15,000kbps (YouTube recommended)
Keyframe Interval	2 seconds (Platform recommended value)
Preset (x264)	“slow” or “medium” (ultra-high quality)
Scaling Filter	Lanczos

AI-enabled automatic improvement method for OBS block noise

Recently, integrating NVIDIA AI technology into OBS has progressed, with a notable example being the “OBS RTX SuperResolution” plugin.

Utilizing AI functions embedded in the GPU, it is equipped with a mechanism to significantly reduce block noise and compression artifacts in real-time.

Even with low bitrate or low-resolution sources, the AI estimates and supplements video details, making it easier to maintain clear and smooth video compared to regular scaling processes.

▼OBS RTX SuperResolution setup method

1. Download “OBS RTX SuperResolution” from the OBS plugin page
2. Open OBS, then select “Filter” menu
　⇒Select the video source to reduce noise (such as game screens or camera videos)
3. Add the “RTX SuperResolution” filter and adjust parameters
　・Upscale Level: Choose how much to adjust resolution (e.g., 720p⇒1,080p)
　・Noise Reduction Intensity: Set the strength of noise reduction (be cautious as an excess can blur details)

AI processing requires certain GPU resources. Be mindful that using it simultaneously with high-load tasks like gaming may result in frame rate drops or processing lag.

Once OBS block noise is reduced, what’s next?

This time, we’ve explained the causes and solutions for block noise occurring in OBS. By optimizing bitrates, encoders, and network speeds, you can achieve clear and smooth video.
Key points to reduce block noise are as follows:

Solution Item	Improvement Method
Bitrate Setting	Set based on platform recommendations (e.g., for Twitch it’s a max of 6,000kbps)
Encoder Selection	If you want to minimize CPU load, choose NVENC; for quality, prioritize x264 (medium or higher)
Securing Network Speed	At least 8Mbps upload speed for 1,080p/60fps

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