Peculiar RAM Issue

[swathe]

Here are the symptoms
1. 4x 4GB RAMs are installed
2. Only 8GB are detected in the BIOS
3. Windows 10 task manager detected 2/4 banks are installed
4. CPUZ detected SPD for all 4x 4GB RAM

Swap RAM in various combinations and confirmed slots nor RAM are faulty. Including putting
a. RAM A and B in Slots 1 and 3
b. RAM A and B in Slots 2 and 4
c. RAM C and D in Slots 1 and 3
d. RAM C and D in Slots 2 and 4.
e. RAM A, B, C, D in Slots 1,2,3,4 and in random positions.

In all combination, only 8GB are detect. And in various combination of (e), SPD detected 4x RAMs with BIOS detecting 8GB.

(a) to (c) are to show slots and RAMs are all working. (e) is to show that BIOS can only detect 8GB.

Any clue?

 

[Yongkit]

Wondering if you have try to clear CMOS for the test?

 

[RLWZ21]

and which borad are you using? i have this issues with one of my old broads where i need to tweak the placement before i can have all rams detected.

 

[swathe]

Tried clearing CMOS, it is the same. And took out battery too in desperation. Old board with no further BIOS update.

The issue happen when I am helping someone to test their RAM.

 

[yusoffb01]

old motherboard may not support 4x 4GB? check the manuf site

 

[Yongkit]

can try check following in windows 10:
1. Click Start and type System Configuration and then press Enter.
2. Go to the Boot tab.
3. Click on Advanced options...
4. Make sure the maximum memory is unchecked.

 

[Yongkit]

One thing to double check with TS wondering if the BIOS showing 4 stick of RAM info (example screenshot below) when all 4 slot used since windows only detected 2 slot?

 

[swathe]

The issue is at the BIOS level not Windows since POST already indicated 8GB only.

It is an old board, has been running 4x 4GB for years until it was taken out for testing.

 

[wwenze]

That happened to me when I overclocked too high i.e. FCLK 1:1 4GHz @ CL16 @ stock voltages

Just to check you're not using some Sandy Bridge era stuff that is limited to 8GB max memory?

 

[swathe]

That happened to me when I overclocked too high i.e. FCLK 1:1 4GHz @ CL16 @ stock voltages

Just to check you're not using some Sandy Bridge era stuff that is limited to 8GB max memory?

Yes, indeed it is Sandy but it was running 16GB ok for a number of years.

 

[tsteo77]

Yes, indeed it is Sandy but it was running 16GB ok for a number of years.

Since rams and slots are fine then must be due to your old motherboard faulty.