F3-14900CL9Q-16GBXL in a GIGABYTE GA-990FXA-UD3

[Beeskee]

I'm trying to use my F3-14900CL9Q-16GBXL DDR3-1866 memory (16 GB) in a GIGABYTE GA-990FXA-UD3 motherboard, and I have an issue where the motherboard resets the memory speed back to 1333 after a cold boot. It isn't resetting any other BIOS settings so it's not the motherboard battery. I'm not sure if there's an incompatibility issue or I don't have things set quite right in BIOS. I do have the latest BIOS update.


There are a lot of memory settings in that BIOS, I'm not sure what to set for all of them.

1T/2T Command Timing - ?
CAS# Latency - 9
RAS to CAS R/W Delay - 10?
Row Precharge Time - 9?
Minimum RAS Active Time - 28?
TwTr Command Delay - ?
Trfc0 for DIMM1, DIMM3 - ?
Trfc2 for DIMM2, DIMM4 - ?
Write Recovery Time - ?
Precharge Time - ?
Row Cycle Time - ?
RAS to RAS Delay - ?


Any suggestions would be appreciated. I'd really like it to save the 1866 memory settings when I turn the computer off, rather than resetting back to 1333. Once it's set, it does stay at 1866 until I turn the computer off, and everything seems to work fine.

[Tradesman]

Does it give any kind or error message at boot or shutdown? Once you set the DRAM freq to 1866, the base timings 9-10-9-28 and CR (Command Timing) to 2T.....they should stay or give an error either on initial boot or possible shutdown. Could try running Memtest on each stick, but if no error coming up, it sounds like a physical mobo or BIOS programming problem that it doesn't hold/maintain the correctly set info.

[Beeskee]

It doesn't give any error when booting up. Sometimes after changing the settings it will say that overclocking failed, it usually happened when I tried different timings. When I specify the provided settings and SPD settings for the rest, it saves.

The board specifications say that it can handle 1866 memory without overclocking. One of the reasons I chose that board is that it is supposed to be able to handle that memory speed. The memory itself auto-detects at 1333.

I'm not sure what to put for the rest of those settings, I'm wondering if those are the problem.


I appreciate your assistance by the way, the quick response time is very nice. Thank you.

[Tradesman]

My fault, I also meant to ask what CPU? The mobo can do many things, but requires a CPU that can also handle it....and there only about a half dozen of the AMD CPUs that can effectively run 1866 sticks.

[Beeskee]

It's the AMD FX-4100 Zambezi 3.6GHz Socket AM3+ 95W Quad-Core - FD4100WMGUSBX

[Tradesman]

I would suggest trying the settings again, but raise the DRAM voltage to 1.55 and add + .06 to the CPU/NB voltage....if that doesn't work possibly check with Gigabyte on what settings they use. Despite all the hoopla AMD pushed about the FX CPUs running 1866 DRAM, they have now changed that position to
"Type of Memory Supported Up to DDR3 1866 " ........ I have been in contact with their tech support, and have been quoted to look in some arcane document, that the CPU's will support 1866 up to 1 DIMM per channel (2 sticks total) for the 8120 and 8150...we have been having numerous folks checking in on running 1866 and having all kinds of trouble....AMD has also told me that if the mobo makers say it will run on their mobo then should check with them, (in other words what the specs show for your mobo, are probably based on running 1866, at 2 sticks with an 8150)......

If the additional voltage doesn't help maybe try 1600, at 8-9-8-27, with standard voltage

[GSKILL TECH]

1T/2T Command Timing - 2T
CAS# Latency - 9
RAS to CAS R/W Delay - 10
Row Precharge Time - 9
Minimum RAS Active Time - 28

Rest AUTO

CPU-NB Voltage +0.1V

Thank you
GSKILL TECH

[Beeskee]

Thank you both for the suggestions. I was able to get everything working at 1600. I have not yet tried the 1866 settings. I may just leave it at 1600, everything seems blazingly fast compared to my last computer.

[Tradesman]

Keep us informed of how things are going

[Beeskee]

Sorry to reopen such an old issue, but I'm having more problems with that FX series processor. Do you have a recommendation for another processor which is compatible with the motherboard and memory I'm using? I appreciate any feedback you have, thank you.

Everything with the memory has been running fine, I'm running it at 1600 with no problems. The issue I'm experiencing is related to the processor line. I'm going to try a BIOS update tonight - hopefully that will fix it temporarily, but at this point I'd rather just replace the processor.

[Tradesman]

What kind of problems? I know the 4100 isn't all that strong of a CPU, but might be able to figure out the problems