x99 extreme6 with 6800k ram issues

So I have a huge issue. I have an extreme6 x99 motherboard ( not the 3.1) that was running a 5820k @ 4.4 with 4x8 sticks running at 2666mhz. Its been that way for months and 100% stable even on the current newest bios 3.2 . This week i picked up a 6800k just to play with and was able to overclock to 4.3 completely stable but I am unable to move the ram up past 2100mhz. I tried every slot and even with 1 stick and anything over 2100mhz it crashes on boot or black screens. I have tried 3 different types of ram, DDR4 2400, 2800 and 3200 clocked down to 2100 works great. I have set manual timings used XMP and changed the clock speed back to 2100 and it works fine. but using any speed other than 2100mhz the pc fails on boot. I have also tried everything stock and 2400 still bombs out. I have tried differnt dividers i am really out of ideas. I put the 5820k back in and still overclocks just fine. So its either the bios or the CPU.. any ideas? I have also messed with the voltages and still nothing. 

wrangler88 wrote: So I have a huge issue. I have an extreme6 x99 motherboard ( not the 3.1) that was running a 5820k @ 4.4 with 4x8 sticks running at 2666mhz. Its been that way for months and 100% stable even on the current newest bios 3.2 . This week i picked up a 6800k just to play with and was able to overclock to 4.3 completely stable but I am unable to move the ram up past 2100mhz. I tried every slot and even with 1 stick and anything over 2100mhz it crashes on boot or black screens. I have tried 3 different types of ram, DDR4 2400, 2800 and 3200 clocked down to 2100 works great. I have set manual timings used XMP and changed the clock speed back to 2100 and it works fine. but using any speed other than 2100mhz the pc fails on boot. I have also tried everything stock and 2400 still bombs out. I have tried differnt dividers i am really out of ideas. I put the 5820k back in and still overclocks just fine. So its either the bios or the CPU.. any ideas? I have also messed with the voltages and still nothing.  Thank you!

It sounds like you might have already installed the Broadwell-E compatible IME software, the Intel Management Engine driver ver:11.0.4.1186, on your board's download page. Essential for over clocking.

Your memory issue is strange, since Broadwell-E processors are universally said to have an improved IMC compared to Haswell-E.

What is the full model number and make of your memory? "4x8 sticks" means what, 4 x 8GB or 4GB x 8?

I have an ASRock X99 Extreme6/3.1, and also now use an i7-6800K with it. When I installed that CPU, I also cleared the UEFI/BIOS with the board's jumper, and removed the battery. That way I had a completely fresh start with the UEFI and NVRAM data.

My standard 2133 memory easily over clocks to 2666 at the same timings as 2133, with my 6800K.

In the DRAM Configuration screen, at the very bottom, find the MRC Fast Boot option. Set that to Disabled. That causes memory training to occur during POST, which will help with memory compatibility.

If you are mixing two or three of your three types of memory together at the same time in the board, I would not expect them to work together well, and nothing can be done to guarantee they can work together.