Asus M5A78L-M wont detect all Kingston RAM sticks

[Caitlyn]

I have Asus M5A78L-M motherboard in my computer and am using it from quite some year. Usually it used to crash with the HD 6000 series graphics card that I had but I replaced it and everything was working fine. After that I did a BIOS update and it worked for a couple of weeks. But recently all of a sudden it is not recognizing 2 of the 4 sticks of Kingston RAM installed in my system. I tried to change the positions of the RAM but to no avail. What could be the problem here? Any ideas

[Russell]

Can you try to raise the DRAM voltage to +0.05 and the CPU/NB voltage to +0.10. It might be possible that the DRAM might be at 1066 and not on optimal configuration. You can even try to reinstall an old BIOS for your motherboard since everything was working fine with it. You should also try to use a single kit of RAM that has been tested by memory manufacturer instead of combining different single DIMMs and getting into trouble.

[Sebastian.j]

Incase the 2 working RAM sticks are working in every memory slot then it simply means that the other 2 RAM sticks might be faulty. I think that your Asus M5A78L-M motherboard runs memory in dual channel, so the RAM is needed to be installed in matching pairs. Check if both the KVR part number and string match on each module and if it is not then there will be some problems working in the dual channel.

[Balamani]

Even I am concluding that your other 2 memory stick might be at fault. You should try to test the RAM sticks with memtest tool and run it overnight to find if it gives any kind of error. If there are any errors then it is confirmed that the RAM sticks are bad. So, if this memory modules are in warranty then you can set those up for a warranty replacement. Also do let us know what error you are getting specifically.