Question BIOS and OS only shows 4 GB of RAM on my laptop but CPU-Z shows 8 GB of RAM. How to fix it?

[MobiusZero]

Hi, I've been having a problem with my laptop. It has a soldered 4 GB DDR4 RAM onboard and I added one 4 GB of DDR4 RAM (it only has one extra slot) years ago
so the BIOS and OS read the total memory as 8 GB.

Then, a month ago I installed 64-bit version of Ubuntu as second OS (i.e: dual-boot) and recently I noticed that my laptop suddenly has become
slower than it used to be. I checked the OS and the BIOS it only shows 4 GB of RAM.

I assumed that the added memory card has become faulty so I bought a 8 GB of RAM with same frequency as the older one.
When I started it for the first time, it showed 12 GB of RAM (i.e.: 4 GB onboard RAM + the new 8 GB RAM). Then, I shut down my laptop and booted it up again. It went back to 4 GB of RAM again.

I checked on CPU-Z and in the SPD tab it detects my 8 GB RAM and same thing with the memory tab but it shows Single channel instead of Dual.
I've tried running memtest86 from USB and the test passed with no errors. I have also tried updating the BIOS, which is EZ Flash, but to no avail. The BIOS menu itself has no memory settings.

Here're the screenshots from the CPU-Z, my PC information, and memtest result.

How do I get it fixed so that the added RAM can be detected by BIOS and OS?

 

[Darkbreeze]

With the memory installed, disconnect power, remove the battery, locate and remove or disconnect the CMOS battery for five minutes. During that five minutes, press the power button on the laptop continuously for 30 seconds to dissipate any residual power in the unit. Reconnect the battery after the five minutes is up. Reinstall the battery. Reconnect power. Power on the unit and go into the BIOS setup program. Choose the option to load the Default or Optimal default BIOS settings. Save settings and exit. Check to see if the memory is now recognized and working normally.

If it is not, then you either have a memory module that is not compatible with your system or that it doesn't "like", or an issue with your motherboard or CPU. Usually these are memory compatibility issues but it may just need to have the hardware tables reset.

 

[Proximon]

With the memory installed, disconnect power, remove the battery, locate and remove or disconnect the CMOS battery for five minutes. During that five minutes, press the power button on the laptop continuously for 30 seconds to dissipate any residual power in the unit. Reconnect the battery after the five minutes is up. Reinstall the battery. Reconnect power. Power on the unit and go into the BIOS setup program. Choose the option to load the Default or Optimal default BIOS settings. Save settings and exit. Check to see if the memory is now recognized and working normally.

If it is not, then you either have a memory module that is not compatible with your system or that it doesn't "like", or an issue with your motherboard or CPU. Usually these are memory compatibility issues but it may just need to have the hardware tables reset.

This seems the most reasonable thing to do. Since it's a fairly new BIOS it could be a bug in the code I suppose. You might want to post on an ASUS support forum if such exists... they might just send you a beta BIOS to try. But only once you try the above.

 

[Darkbreeze]

Good point. And if there IS a BIOS update available for that system, it might be a good idea to update. Often BIOS updates include changes to memory compatibility even if it's not listed.