32 GB of ram, only 16 is read by bios, windows and ubuntu

[s903s]

Hi everyone, I have an issue since some years that I have never succeeded to understand on what it depends I have a computer assembled by me with these features:
Processor: Intel i73770
Motherboard: asus P8z77-v deluxe
Ram: 32 GB, corsair CMz32GX3M4X1866C10
GPU: Gainward geforce 680
When I have assembled this pc for some months both windows and ubuntu they was reading 32 GB of ram fully. After some months suddenly it reads 16 GB of ram, from bios also if the rams are 1866 mhz I can take them only maximum to 1600 mhz. I can't understand why I have this issue and how to solve it. I attach to this conversation some screen of cpuz and windows properties.
Thank you for helping

[DaveLembke]

So CPU-Z shows all ( 4 ) 8GB sticks installed and initialized, an Ubuntu system properties only shows 16GB. That looks like a bug maybe in Ubuntu as for if the other 16GB wasnt getting addressed then CPU-Z wouldnt detect them. This is the first I have heard of this. Unfortunately I only have a server with 16GB RAM and none higher to test my hardware against greater than 16GB to see if its a bug that repeats if I installed your version of Ubuntu.

Could you have 16GB of RAM shared elsewhere such as 16GB system RAM shared with the GPU or a RAM Drive, the OS might only be showing whats available to it if its allocated elsewhere?

Have you run Memtest86 on the RAM to make sure that all is healthy?

[patio]

Sounds like CPUz isn't detecting the multiplier...

How does Speccy report it ? ?...or System Info for Windows ? ?

[s903s]

So CPU-Z shows all ( 4 ) 8GB sticks installed and initialized, an Ubuntu system properties only shows 16GB. That looks like a bug maybe in Ubuntu as for if the other 16GB wasnt getting addressed then CPU-Z wouldnt detect them. This is the first I have heard of this. Unfortunately I only have a server with 16GB RAM and none higher to test my hardware against greater than 16GB to see if its a bug that repeats if I installed your version of Ubuntu.

Could you have 16GB of RAM shared elsewhere such as 16GB system RAM shared with the GPU or a RAM Drive, the OS might only be showing whats available to it if its allocated elsewhere?

Have you run Memtest86 on the RAM to make sure that all is healthy?

Also on windows and other oses gives the same issue, windows for example says to use only two slots of 4, I have tried memtest86 pro, memtest86+ and windows memtest I think the ram is healthly cause I have tried to put it on another pc too

Sounds like CPUz isn't detecting the multiplier...

How does Speccy report it ? ?...or System Info for Windows ? ?

Speccy reports 32 GB of ram and 4 slots installed I attach here the speccy report
 

[attachment deleted by admin to conserve space]

[patio]

Then if Speccy reports it properly you are fine...

[s903s]

Then if Speccy reports it properly you are fine...

No cause I can't use that ram to create a virtual machine cause for example windows doesn't detect it and windows says that it uses only 2 of four slots :

[Calum]

First thing to try is to boot with each stick of RAM individually, to make sure all 4 sticks are working.  Add them back in, one at a time, in the correct slots, and see what happens.  If you now have 32GB, problem solved.  If not, Take out your CPU and check very carefully for bent pins.  If the socket all looks OK, reseat the CPU, and check how much RAM shows up now.  If you have an aftermarket heatsink, make sure you're not tightening it too far, that can cause this issue as well.

After you've tried the above, post back and let us know the results.  Hope this helps

[Salmon Trout]

Add them back in, one at a time, in the correct slots, and see what happens.

You MUST do this with the AC power lead disconnected from the PSU! When removing or inserting RAM sticks. Otherwise you can kill RAM or motherboard or both.

[s903s]

I have resolved flashing ME