990FXA-UD3 RAM issue

[TymmVonD]

Running XMP profile 1, Windows 8.1 shows 8GB(3.96GB available). CPU-Z confirms is running single channel config. I tried setting from 1866 to 1600, still single channel.

[helping]

It shouldn't really matter, but do you have them in the correct channels as labeled on the diagram on the board?

 

Might also just need a reseat

[Sarcasm]

Did you even populate the modules in the correct order?

[Altecice]

Silly question.... But are you running a x86 or x64 bit OS?

[TymmVonD]

Went over the manual. Same as my other boards. 2nd and 4th slots from left to right. I have swapped them with each other and I have ran them in true single channel, one stick at a time.

[TymmVonD]

Silly question.... But are you running a x86 or x64 bit OS?

It had me thinking that as well as I had done the upgrade from Win8 over the store. My program files has both folders. 32  bit does support dual channel though, right?

[Altecice]

press Windows key + PauseBreak key to bring up system info and it will state there if its a 64bit OS.  

 

but i suggest you read your mobo manual and check if the RAM you have is on the QVL and if there is some order you need to place them in.

[TymmVonD]

Gigabyte's manual is a bit contradicting. On one page it says Channel A is 2 & 4 Channel B 1&3. On the next page it diagrams dual channel config-

 

                                                                        4 2 3 1

                                         two modules            x 0 x 0

                                                                        0 x 0 x

                                        quad mod                 x x x x

 

In slots 3 & 1 according to the diagram, it's giving me all 8 gigs, but under CPU-z it still says single channel and lists timings as 4-5-5-15. WTF. I have XMP timings set manually at 9-10-9-27 2T.

 

For test purposes I set it to 1600 9-9-9-24, still single channel, but all 8 gigs show again.

[TymmVonD]

Tested 4 sticks indivdually. Slots 2 and 4 wont POST in single stick config. Gigabyte tech suggested checking cpu pins. Pins fine. Board RMAd. M5A99 Pro coming overnight.