I have an ASRock X79 Extreme 9.

 

For years I had 32Gb RAM (4 sticks @ 8Gb each), G.SKILL Sniper F3-1600C9Q-32GSR.

 

I had installed the sticks in Slots DDR3_A1 and DDR3_A2 (items 2 and 3 on Page 12 of the Manual) and DDR3_C1 and DDR3_C2 (items 14 and 13 on Page 12 of the Manual).

 

My OS is Windows 10 Pro x64 and everything worked fine.

 

Then I got the bright idea to upgrade the RAM to 64Gb.

 

I got a 64Gb matched kit (8 sticks x 8Gb each) of Corsair Vengeance CMZ64GX3M8A1600C9.

 

Once I installed all the sticks and booted up, the post would not go past code "b7" or "67" (it is impossible to tell the difference with those red LED indicators).

 

No matter how I switch around the 8 sticks, I still get that same "b7" or "67" error code.

 

I thought some of the sticks might be defective, so I reverted to my former 4-slot 32Gb configuration I noted above (Slots DDR3_A1, DDR3_A2, DDR3_C1 and DDR3_C2), and started using various combinations of the Corsair sticks.

 

No matter how many combinations of the Corsair sticks I used in the 4-slot 32Gb configuration (DDR3_A1, DDR3_A2, DDR3_C1 and DDR3_C2), the board booted up perfectly each time.

 

Thus, I am fairly certain that none of the Corsair sticks is defective.

 

So does anyone have any insight about how to get past the "b7" or "67" error when all 8 sticks are installed?

 

Why would the board work perfectly with only 32Gb RAM installed on 4 slots, and then keep reporting that "b7" or "67" error with 64Gb RAM installed on all 8 slots?

 

I am totally stumped.

 

Any advice would be most appreciated.

 

Thanks in advance.