Weird RAM fault

I have 4 x 4gb ddr3 ram modules fitted to my desktop.

I have started to find that the amount the system recognises seems to change of its own accord.

Yesterday i started my machine and my system reported 16 GB installed but only 12 useable.

I then had to do a restart due to a windows update and it then said 16GB installed and 16GB available.

I have just started my system and it now says 12GB installed but only 8GB useable.

I think it may be a faulty module that works when it sees fit. But with it now saying 12 installed and only 8 useable I'm not sure.

I have attached a shot of the system info screen and resource monitor from now.

Any help, ideas, tips would be appreciated.

Paul

Just to show what I mean, not 10 minutes later after a restart we are now back to 16Gb available.

paulpies84 said:

Just to show what I mean, not 10 minutes later after a restart we are now back to 16Gb available.

Click to expand...

Based on the two images in your previous posts, it isn't likely that this a RAM fault; both images show 16GBs memory in total. One image shows about 12GBs available and 4GBs of hardware reserved, the other image shows 16 GBs available and only 18MBs for hardware reserved.

Hardware reserved memory allocation is controlled by the BIOS, or UEFI, and not available for Windows but reported nonetheless. You should look into the BIOS how much memory is allocated for various hardware and change it, if available. Alternatively, a BIOS update usually resolves excessive memory reservation.

It is also possible that you have some flash device(s) connected at boot time, that request 4GBs memory reserve for its operation. This would be easy to test, just disconnect the flash device prior to booting and check the memory utilization.