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RAM issue / shared system memory (Gigabyte 78LMT-USB3 Rev. 6.0)


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RAM issue / shared system memory (Gigabyte 78LMT-USB3 Rev. 6.0)
« on: January 06, 2019, 03:19:22 pm »
I am seeking help with my RAM support for this board. Basically what has happened is that previously about a year ago I have had an issue with recognised RAM. What the issue was that out of the 16 gigabytes of RAM installed, 8 was hardware reserved. I have eventually got it working, however. After Windows fall update in 2018 the usable RAM has locked it's self again. To half of the previously installed amount, and no commonly known fixes are working. Therefore I have been forced to run the memory in dual channel in order to use all of the 16GB installed. However upon accidentally finding out, running in dual channel, has somehow forced half of the RAM to be issued as shared hardware to a PCI-E GPU. The GPU I am using Nvidia GTX 970 which comes with 4GB of VRAM out of the box, and then gets an extra 8GB from the system. Now I am kind of confused as to why this has happened? Since either way I am only using half of the installed memory. I have suspected a possibility of the RAM sticks being damaged, however the system boots with either one of them, and a compression test has been completed successfully indicating they are working as intended. What I however have found suspicious is the fact that the system only boots, if the RAM sticks are in the first two slots from the right. On the PCB they are labelled 3 and 4. However in BIOS those exact slots are recognised as 2 and 4???? This leads me to the conclusion of a bug within the BIOS version it's self? If that is the case, what would explain the other two dimm slots not functioning as intended?

*Set up I am using*
CPU: AMD FX-8320
Mobo: Gigabyte 78LMT-USB3 Rev. 6.0
RAM: Corsair Vengeance Pro 16GB 2x8GB 1600MhZ (Currently in dual channel)
Bios version: F2

Task managers reading while having the RAM in dual channel:
RAM settings in BIOS:
« Last Edit: January 06, 2019, 04:57:16 pm by SynX »


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Re: RAM issue / shared system memory (Gigabyte 78LMT-USB3 Rev. 6.0)
« Reply #1 on: January 07, 2019, 03:24:46 pm »
Issues such as this are the exact reason why I stopped using AMD in 2003.  You have other problems. 

You said your Oct update failed.  So the integrity of your OS install is now also brought into question.

What happens if you perform a fresh install of build 1809?  Do you get all 16GB?

There is nothing to gain, fighting with the OS.

Board is 6 yrs old and no BIOS development for the last 4-5 yrs. 
Z390 AORUS PRO (F10) \850w, 9900K, 32GB GSkill TriZ RGB - 16-18-18-38, RTX 2080 FTW3 Ultra, 960 Pro_m.2, W10 2004
Z370-HD3P (F5) \750w, 8350K, 8GB LPX 3200 - 16-18-18-38, GTX 970 FTW SC, Intel SSD, 2TB RAID1, W10 2004
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