1866 RAM prevents boot at 1866

[derpinstein]

Mobo: ASRock 990FX Extreme3
Memory: F3-14900CL9D-8GBSR (2x4GB)
CPU: AMD FX-8120 stock speed/voltage
No OC at all. The two sticks are in slots B1/B2 because A1/A2 are covered by the CPU cooler. I don't know if that makes a difference.

The RAM was detected in the mobo at 1600 MHz, but many reviews for it on Newegg said it would.

I went into the BIOS to increase to 1866 MHz, but that caused Windows to BSOD before it could boot up fully.

I took the stock voltage on the RAM from 1.5v to 1.6v in increments, but that did nothing for the stability.

I then double checked the CAS settings to make sure they were within the range, and they were the Newegg product specified 9/10/9/28.

I am not sure what else to try, as everything is stock except the 1866 MHz.

Is it simply bad RAM? Is it the memory controller not liking being loaded heavily on the B1/B2 channels? -I know AMD CPU's memory controllers were a bit derpy in the Athlon/Phenom series - Any help is appreciated!

[Tradesman]

Can you post your BIOS settings, especially voltages, timings and frequencies. i.e. for 1866 normally will want CPU/NB freq about 2600 and CPU/NB voltage 1.2 or a little higher, may also have to raise DRAM voltage

[sHOOT-mE-damIT]

You have to use A1 and B1 or A2 and B2 this is what it says in the motherboard manual.

Check that you have the latest bios.

Go to http://www.asrock.com/mb/overview.as...0FX%20Extreme3

Use a usb flash drive and get the latest bios option. make sure you read how to do this
all the info is at there site.

Sorry Tradesman just know this system.

[Tradesman]

No problems from me, I love it when folks jump in and help, cuts my workload

[karakistou]

Sorry to bump this thread but I have the same problem here.

I bought Ripjaws Z F3-14900CL9Q-16GBZL, so 4*4GB supposed to run at 1866MHz.

My Sabertooth x79 recognize it as a 1600MHz ram, and if I change it to 1866MHz I get a BSOD when windows boot. I have the latest version of the BIOS, and I have a i7 3930k overclocked with turbo at 4.5GHz.

Idle, CPU voltage is 0.944 V, frequency is 1200MHz.
In full load, it goes to 1.376 V, 4.5GHz.
DRAM Voltage is at 1.5V, as written on the RAM specs.

I use the right slots as described on the motherboard manual.
Does anyone have an idea about how to fix this? What should I change to make it work? the voltage?

Thank you.

[Tradesman]

Have you enabled and tried XMP

[karakistou]

I tried XMP overclocking with default values and it works at 1866MHz, thank you!

[Tradesman]

Great! Glad to hear it, with some mobos you often think you have XMP going but need another step here or there, glad all is well