Question RAM upgrade not detected by BIOS or Windows, but detected by CPU-Z and Memtest86 ?

[AliceMegumi]

Hello,

Hello, I want to ask about my laptop which has a problem in the RAM section. I bought Kingston 4GB SODIMM RAM and installed it into my laptop. But after I installed it in one of my laptop's RAM slots, the RAM was not detected in the BIOS or in my Windows system. But when I use programs like CPU-Z and Memtest86, my RAM is detected with a 4GB RAM product (I'll provide detailed photos of my new RAM below). After I tried to remove my new RAM, my laptop can still turn on as usual by using the RAM already installed in the motherboard. In that case, what part is the problem in terms of increasing the RAM size on my laptop? Is it the RAM, the RAM slot or my motherboard?

ASUS A456UQ Laptop

Specification:
Intel i7-7500U Kabylake
RAM: 4GB
Nvidia Geforce 940 MX 2GB
Windows 10 Pro 64-Bit

My detailed laptop specification and RAM information by CPU-Z :

https://imgur.com/a/BCeVLq1

View: https://imgur.com/a/BCeVLq1

 

[Colif]

it doesn't make any sense that any windows programs can see ram if the BIOS itself can't. Windows uses the bios?? it can't see something bios can't

can you show screenshots of bios where it doesn't see ram? same with windows?

curious how system information isn't showing the 2gb that is on motherboard?

 

[ValdikSS]

"SPD" tab in CPU-Z only reads the information provided in the RAM module's EEPROM chip, directly.

You've inserted 2400 MHz RAM which does not have SPD profile for lower frequencies, while your laptop expects 2133 MHz RAM.

 

[AliceMegumi]

"SPD" tab in CPU-Z only reads the information provided in the RAM module's EEPROM chip, directly.

You've inserted 2400 MHz RAM which does not have SPD profile for lower frequencies, while your laptop expects 2133 MHz RAM.

Okay, maybe i will try another RAM with 2133 MHz frequencies.

 

[AliceMegumi]

it doesn't make any sense that any windows programs can see ram if the BIOS itself can't. Windows uses the bios?? it can't see something bios can't

can you show screenshots of bios where it doesn't see ram? same with windows?

curious how system information isn't showing the 2gb that is on motherboard?

As a ordinary person in this expertise, i can't explain properly with the proper word, but all i can say is in the ASUS BIOS only showing 4GB RAM without any detailed information for all RAM inserted in the laptop.