11-20-2017 03:12 AM
I have changed the factory default 16GB (2x8GB) with 2x 16GB CT16G4SFD8213.
Now Windows 10 x64 reports only 25.4 usable from the 32GB. Resource Monitor indicates that the missing memory is reserved for Hardware but there is no hardware that reserves memory (No external devices, no SSD with rapid mode, the Nvidia graphics adapter has dedicated memory)
When I use any of two DIMM's alone and not in combination Windows 10 reports 15,8 GB available memory so this issue does not appear with only one 16GB DIMM.
Is the combination of these two DIMM's in a XPS 15 9950 an unsupported config causing Windows 10 to block memory it can not handle as hardware reserved?
11-20-2017 02:36 PM
@dnyvdm I am sorry for the issues that you have experienced after installing your RAM. I would recommend checking to see if Windows memory lock is limiting the memory. To check if the Windows memory lock is limiting the amount of memory Windows can see,
1. Click on Start.
2. Type MSCONFIG in Search and click OK.
3. This will open the System Configuration Utility. Click on the BOOT tab.
4. Click on the Advanced Options... button
5. If the /MAXMEM= box is checked, please uncheck it.
6. If it isn’t already checked, check it now and enter your total amount of memory in MB (e.g. 8192 for 8GB) and click OK.
Please let us know if you have any other questions or concerns.
11-21-2017 01:57 AM
I tried both options, the issue remains. What I do notice is that with the option checked and the maximum memory selected (32GB) after a reboot the settings has changed to enabled with '0' memory. The option unchecked still has only 25.4GB usable memory unfortunately.
11-27-2017 01:25 AM
Switched the DIMM's is in an other XPS 15 9550 at my employer and that XPS did not have this issue, so this seems to be a hardware issue with the Dell XPS 15.