How do you know the maximum write/read speed of the microSD slot in a laptop?


rambomhtri

Member
Member
Local time
10:52 AM
Posts
25
Location
Bowie, Arizona
OS
Windows 11 Home (24H2, build 26100.3037)
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:
1738709107580.webp

1738709468246.webp

Realtek PCIE Card Reader from HWInfo:
1738709189743.webp
1738709207169.webp

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.
1738707857660.webp
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.

1738710329041.webp

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.
 
Last edited:

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
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:
View attachment 124268

View attachment 124273

Realtek PCIE Card Reader from HWInfo:
View attachment 124269
View attachment 124270

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.
View attachment 124267
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.

View attachment 124276

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.
Reality is sdcard speed card claims are never met in reality, particularly whn transferring a lot of data. In the real world, you are lucky to get 50% of clasims. 80 MB/S is pretty good.
 

My Computer

System One

  • OS
    Windows 11 Pro + Win11 Canary VM.
    Computer type
    Laptop
    Manufacturer/Model
    ASUS Zenbook 14
    CPU
    I9 13th gen i9-13900H 2.60 GHZ
    Motherboard
    Yep, Laptop has one.
    Memory
    16 GB soldered
    Graphics Card(s)
    Integrated Intel Iris XE
    Sound Card
    Realtek built in
    Monitor(s) Displays
    laptop OLED screen
    Screen Resolution
    2880x1800 touchscreen
    Hard Drives
    1 TB NVME SSD (only weakness is only one slot)
    PSU
    Internal + 65W thunderbolt USB4 charger
    Case
    Yep, got one
    Cooling
    Stella Artois (UK pint cans - 568 ml) - extra cost.
    Keyboard
    Built in UK keybd
    Mouse
    Bluetooth , wireless dongled, wired
    Internet Speed
    900 mbs (ethernet), wifi 6 typical 350-450 mb/s both up and down
    Browser
    Edge
    Antivirus
    Defender
    Other Info
    TPM 2.0, 2xUSB4 thunderbolt, 1xUsb3 (usb a), 1xUsb-c, hdmi out, 3.5 mm audio out/in combo, ASUS backlit trackpad (inc. switchable number pad)

    Macrium Reflect Home V8
    Office 365 Family (6 users each 1TB onedrive space)
    Hyper-V (a vm runs almost as fast as my older laptop)
Reality is sdcard speed card claims are never met in reality, particularly whn transferring a lot of data. In the real world, you are lucky to get 50% of clasims. 80 MB/S is pretty good.
1738712102577.webp

From a review with a proper usb3 adapter, Samsung pro plus microSD claiming 130/180MBps write/read... perfectly checks out...

Unless you can't interpret data or the speeds are clearly an over exaggeration, YES, claimed speeds can be met just fine if you have proper hw. What happens is people face my scenario and instantly blame Samsung for "cutting half the speed". Yeeeeah, sure, magically. It can't be your port limits, no, it's evil company misinforming.

In case you have doubts I'm telling you Samsung is not making anything up and people get 130MBps with my card. I know it's my laptop fault or some proprietary incompatibility.
 

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
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.
sounds like you already answered your own question. if its propriety, then you MAY find one very obscure third party vendor that can meet the maximum output... but between time wasted/money spent in doing so...
 

My Computer

System One

  • OS
    Windows 11 Pro
sounds like you already answered your own question. if its propriety, then you MAY find one very obscure third party vendor that can meet the maximum output... but between time wasted/money spent in doing so...
No, I found one single example of one single brand model with one single brand adapter. But, as you can see in my message before yours, that's a Kingston Adapter with another Samsung microSD and it reaches the claimed speeds by Samsung. So, it's not that simple, besides... if there are no Realtek microSDs, and there are no Samsung or Kingston or Sandisk card readers in laptops... it makes no sense.

Basically I am trying to know where can I check my card reader max speeds (literally the title), and then what card can go in it without any limitations due to incompatibility to the specification or protocol or whatever that takes full advantage of said microSD.
 

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
RTS525A dates back to at least 2019.. maybe 2018. brief search around a few forums says the cap is 100mb/s
 

My Computer

System One

  • OS
    Windows 11 Pro

Latest Support Threads

Latest Tutorials

Back
Top Bottom