Hello, I have the laptop of my second system, a modern 2023 fast ASUS laptop, and it has a microSD reader. Apparently from what I can tell from the driver, it's from Realtek and the model is RTS5250S, or maybe an RTS525A, I can't tell. I want to know what's the maximum speed of the microSD port, I mean transferring seq data like a 16GB video.
This is from my laptop's official drivers page:


Realtek PCIE Card Reader from HWInfo:


I just bought a Samsung Evo Plus 256GB 2023 which is a Class 10, U3, V30, A2, UHS-I card that goes around 120-130MB/s write/read.

When transferring a 16GB video, it writes on the microSD at 70MB/s and reads at about 78MB/s, which is WAY worse than expected.
I bought a Kingston MobileLite Plus USB 3.1 (actually USB3.2 Gen 1) microSDHC/SDXC UHS-II adapter which tops at more than 300MB/s (seen reviews online), just to check how fast is the microSD, and turns out I get 80MB/s read/write.

Then I discovered that if you have a card from Samsung and want to use the top speed, you need a Samsung adapter, not a Kingston one, and it goes the same with many other models from other brands... disgusting.
So... I don't know if I should keep buying other brands that promise to get write speeds of 130-180MB/s like SanDisk or Lexar or Kingston until suddenly one magically takes full advantage of my micrSD port, I don't know if I should buy UHS-I or UHS-II... this is all really obscure and very badly standardized. Look at SATA, you got the port speed by SATA I, II, III, USB the same, M.2 ports too with nVME 1.3, 1.4, PCIe Gen3, Gen4... but for microSD ports, it is "laptop with microSD reader". Go figure.
This is from my laptop's official drivers page:


Realtek PCIE Card Reader from HWInfo:


I just bought a Samsung Evo Plus 256GB 2023 which is a Class 10, U3, V30, A2, UHS-I card that goes around 120-130MB/s write/read.

When transferring a 16GB video, it writes on the microSD at 70MB/s and reads at about 78MB/s, which is WAY worse than expected.
I bought a Kingston MobileLite Plus USB 3.1 (actually USB3.2 Gen 1) microSDHC/SDXC UHS-II adapter which tops at more than 300MB/s (seen reviews online), just to check how fast is the microSD, and turns out I get 80MB/s read/write.

Then I discovered that if you have a card from Samsung and want to use the top speed, you need a Samsung adapter, not a Kingston one, and it goes the same with many other models from other brands... disgusting.
So... I don't know if I should keep buying other brands that promise to get write speeds of 130-180MB/s like SanDisk or Lexar or Kingston until suddenly one magically takes full advantage of my micrSD port, I don't know if I should buy UHS-I or UHS-II... this is all really obscure and very badly standardized. Look at SATA, you got the port speed by SATA I, II, III, USB the same, M.2 ports too with nVME 1.3, 1.4, PCIe Gen3, Gen4... but for microSD ports, it is "laptop with microSD reader". Go figure.
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My Computers
System One System Two
-
- OS
- Windows 11 Home (24H2, build 26100.3037)
- Computer type
- PC/Desktop
- Manufacturer/Model
- ASUS
- CPU
- AMD Ryzen 9 7900 (65W)
- Motherboard
- ASUS ROG Strix X670E-E Gaming WiFi (BIOS 2604)
- Memory
- 2x16 = 32GB G.Skill Trident Z5 Neo DDR5 6000MT/s CL30 (AMD EXPO I)
- Graphics Card(s)
- nVIDIA ASUS RTX 4060 Dual OC (Quiet mode)
- Sound Card
- Realtek ALC4080 USB interface 32-Bit/384 kHz
- Monitor(s) Displays
- HP EliteDisplay E233 23"
- Screen Resolution
- 1920x1080 Full HD
- Hard Drives
- Samsung 990 Pro 1TB
Samsung 970 Evo Plus 500GB
WD Red NAS 4TB HDD
- PSU
- Corsair SF750 80 Plus Platinum 750W (2024, ATX12V v3.1)
- Case
- Wood Custom
- Cooling
- AMD Wraith Prism
- Keyboard
- ReDragon Mitra K551 (lubed Outemu White Silent switches, ABS double-shot keycaps)
- Mouse
- Logitech G502 (custom switches and lubed mechanisms)
- Internet Speed
- 1Gbps, Intel AX210 WiFi6E BT5.3, Intel I225-V 2.5Gbps
- Browser
- Chrome, Opera, Edge, Firefox
- Antivirus
- Windows Security
- Other Info
- Arctic MX4 thermal compound
-
- Operating System
- Windows 11 Home (24H2, build 26100.3037)
- Computer type
- Laptop
- Manufacturer/Model
- ASUS/Zenbook 14 OLED UX3402VA
- CPU
- Intel Core i5 1340P
- Motherboard
- Intel Alder Lake-P PCH (BIOS UX3402VA.306)
- Memory
- 4x4 = 16GB LPDDR5 SDRAM
- Graphics card(s)
- Intel Iris Xe (80EU)
- Sound Card
- Intel Raptor Lake-P/U/H PCH - cAVS (Audio, Voice, Speech)
- Monitor(s) Displays
- Samsung SDC4171 14" OLED
- Screen Resolution
- 2880x1800
- Hard Drives
- Samsung 990 Pro 1TB
- PSU
- 65W Adapter
- Internet Speed
- 1Gbps