Tesla’s autonomous driving technology is developing around HW3 (hardware 3.0) and HW4 (hardware 4.0). HW3 is a full self-driving (FSD) computer introduced in 2019,offering 36 TOPS performance per second in the 14nm process.

HW4 is a 5nm process -based hardware applied as 2023, with a 300 ~ 500 TOPS computing capacity. These two hardware differ in storage structure and software update and affect the implementation of autonomous driving functions. In this article, the partition size of the HW3 and HW4 is compared, and it analyzes the size of the software update by model to explore its meaning.

Comparison of the Partition size of HW3 and HW4

The partition size determines the storage division structure for software execution and data storage. Tesla uses NAND flash memory in HW3 and HW4 and stores operating systems (OS), map data, and logs. The specific partition size was not officially disclosed.

HW3 Partition Size:

the HW3 uses 128GB storage, and the firmware partition size has been expanded from 1GB to 2GB in 2021 and 3.5GB at the end of 2024. this is the result of the lack of existing partitions due to the increase in neural networks (NN) in size, according to the analysis of X users. The 3.5GB partition is also reaching its limit. The total partition structure to be presumed is as follows:

OS and applications: about 20-30GB (software and settings, estimates)
Map data: about 40 ~ 60GB (high resolution map, estimated value for FSD)
Log and Dash Cam: about 30 ~ 50GB (driving data and video, estimates)

HW3 relies on data compression and optimization with limited computational capacity (36 TOPS).

HW4 Partition Size:

HW4 uses 256GB storage and processes 9 5MP cameras and radar data. The firmware partition is set to 8GB, but according to @GreenTheonly, the latest FSD V13 neural network (Node B 7.5GB, Node A 2.3GB) is close to the 8GB partition limit. The total partition structure to be presumed is as follows:

OS and applications: about 30-40GB (complex AI model, estimated)
Map Data: About 80 ~ 100GB (High Resolution Data, Estimation)
Log and Dash Cam: About 80 ~ 100GB (High Resolution Video and Log, Estimation)

HW4 is designed for dual redundancy and high resolution data processing.

Comparative Summary:

The storage of HW4 is twice the HW3 (256GB vs 128GB), and the firmware partition is 8GB, which is larger than the 3.5GB of HW3. However, HW4’s neural network size (7.5GB) is close to the 8GB partition limit, which may be necessary to expand partitions similar to HW3. The entire partition size is estimated to be about 1.5 to 2 times larger than HW3, but the exact data is not confirmed.

HW4’s neural network size is close to the 8GB partition limit, which may be necessary to expand partitions similar to HW3.

Software Update Size Comparison by model

Tesla’s over-the-air update varies depending on the vehicle model (Model S, 3, X, Y, Cyber Truck) and hardware (HW3 vs hw4), and the file size is not officially released.

HW3 vehicle software update:

the latest FSD version of HW3 vehicles (Model S, 3, X, Y) is V12.6 (2024.45.25.10), and the neural network size is node A 1.2GB and Node B 3.1GB, and the OTA update size is estimated to be about 2 ~ 3GB. This update is:

FSD function stability improvement
Optimization of cameras and navigation
HW3 minimizes the operation load with a lightweight code.

HW4 Car Software Update:

The latest FSD version of HW4 vehicles (Model 3,Y,Cyber Truck) is V13.2.9 (2025.14.6), and the neural network size is node A 2.3GB and Node B 7.5GB, and the OTA update size is estimated to be about 4 ~ 6GB. this update is:

High resolution (5MP) camera and radar data processing
strengthening FSD non -supervisory function
HW4 supports large AI models.

Differences by Model:

Model S/X: HW3 is 23GB and HW4 is 46GB (estimated).HW4 first supports FSD V13.
Model 3/Y: HW3 is 23GB and HW4 is 46GB (estimated). HW4 is a priority for new functions.
Cyber Truck: HW4 dedicated, 5 ~ 6GB (estimated). FSD v13.2.9 Basic support.
The update size is estimated and reflects the increase in neural networks of HW4.

Analysis: The Meaning of Partition Size and Update Size

The difference in partitions and updates in HW3 and HW4 shows Tesla’s autonomous driving strategy and technical limitations.

HW4’s Technical Advantage: HW4 supports FSD V13 with its computational ability (300 ~ 500 TOPS) and 256GB storage, which is 3 ~ 8 times higher than HW3.Nine 5MP cameras and radars produce high resolution data, while the 8GB firmware partition processes a large neural network (Node B 7.5GB). However, according to @GREENTHEONY, the 7.5GB neural network is close to the 8GB partition limit, and the need for expanding partitions similar to HW3 is emerging. This is the foundation for fully autonomous driving, such as Robo Taxi.

Limit: HW3 is 36 TOPS and 128GB storage, making it difficult to run FSD V13 (Node B 7.5GB). The firmware partition was expanded from 1GB in 2019 to 3.5GB in 2024, but it is still facing limitations. tesla optimizes V12.6 for HW3 and attempts back porting, but is likely to limit functionality.Illon Musk said in the third quarter of 2024 that HW3 would provide HW4 upgrades to FSD buyers if they failed to run without self -driving. Though, due to the difference in the form factor of HW4, the upgrade cost and complexity are high.

Strategic Priority: HW4 vehicles are first distributed to FSD V13, and HW3 maintains V12.6. This shows Tesla’s strategy to reduce hardware fragmentation by focusing resources on HW4. @GREENTHEONY’s posts suggest that HW4’s 8GB partitions can also be insufficient due to the increase in neural networks, and that Tesla is having a similar partition management problem to HW3.

Consumer and Market Impact: HW3 vehicle owners can complain by limiting FSD functions, and upgrade incentives to HW4 increases. The performance of HW4 attracts new customers, but the suspension of HW3 support can lead to a drop in consumer trust and legal risks (see NHTSA examination case).

HW4 is a 256GB storage and an 8GB firmware partition that is superior to HW3 (128GB, 3.5GB), and supports the FSD V13 with nine 5MP cameras and radars. However, due to the increase in neural networks, HW4 is also facing partition limits. The OTA update size is larger than HW3 (2 ~ 3GB), which is larger than HW4 (4 ~ 6GB), which reflects a large AI model. Tesla should fulfill the HW3 upgrade promise and maintain trust and lead the autonomous driving market with HW4 -oriented innovation. In the future, HW3 support policies and HW4 partition management trends are noted.