P68 Extreme3 Gen3 - RAM Troubles, Bios Questions

Updating to a new UEFI/BIOS version is an old and simple suggestion for dealing with memory compatibility issues.

This method assumes or depends upon improved memory compatibility changes being part of one or more UEFI/BIOS updates, and that they will apply to your situation. I will tell you now there is NO guarantee updating your BIOS will make your memory work at 2133. More on that later.

In the case of your board, which I assume is a Z68 Extreme3 Gen3 (not P68 as in your thread's title..., no such Intel chipset exists. The P67 chipset exists, but your board is a Z68 model), currently has the 1.20 UEFI version, a very early version.

At this point, only the Sandy to Ivy Bridge compatibility version and beyond BIOS versions exist. So you have no choice but to apply that version, and hope the other updates it has from other updates over time will help with your memory issue. You're not making this easy for yourself.

First, you MUST apply the 2.10 UEFI/BIOS version, you CANNOT skip it. Well, you can, but you will then corrupt your BIOS chip to the point it will need to be replaced. This version will work fine with your Sandy Bridge processor.

As my guide on the other ASRock forum website describes, updating to this BIOS version must be done correctly, which is really simple. But you MUST follow a few simple steps.

First is use the Instant Flash update method only. That means putting the unzipped BIOS file on a USB flash drive, and put the USB flash drive in a USB 2.0 port on the board's IO panel.

You then go into the BIOS and run the Instant Flash tool, which is in the Advanced screen in your BIOS.

When Instant Flash is complete, you will be prompted to press enter to restart the PC. Do that, but you MUST remember to leave the USB flash drive with the BIOS file in the PC, DO NOT REMOVE IT!! That is the only procedure you need to follow to get this BIOS update right.

Once Windows has completely booted to the desktop after the BIOS update, you may then remove the USB flash drive.

At that point you must install the new version of the Intel IME software, ASRock's AXTU if you use it, and the Intel video driver, if you use the integrated graphics.

You mentioned preparation for VR... so what version of Windows are you using?

One thing that is not clear to me is are you ONLY using the new 16GB of G.SKILL 2133 memory in your board, or is it being used with memory you have used in the past?

If you are mixing the new memory with even the same model of memory you have used in the past, there is no guarantee that mixing the two kits will work well for you. Over time, memory manufactures change the memory chips used in the various models of memory they have. Mixing old and new memory kits of the same model will be pure luck if they use the same memory chips, and be compatible at higher speeds.

Your i5-2500K, or any other i5 or i7-2000 series processor, is rated to work with memory speeds up to 1333. (The memory controller is part of the CPU, and is not located elsewhere on the mother board.) That is all Intel guarantees, 1333. All memory speeds above 1333 are memory over clocks, which of course are not guaranteed.

Larger capacity DIMMs, like your 8GB models, are more difficult to use at higher speeds. It is also more difficult to use larger amounts of memory at higher speeds.

When you installed your new memory, did you clear the CMOS/BIOS before you started the PC again? If not, you must do that any time you change your memory, or even move it to different slots. Clearing the CMOS/BIOS is very important, if you are lucky it may be the only thing you need to do.

You should be using the A2 and B2 memory slots when using two DIMMs.

You said you tried using the XMP profile. What was the memory voltage set to with XMP? If it was 1.5V, you'll need to set it higher. Try 1.55V, up to 1.6V.

You may also need to increase the VCCSA and VTT voltages to get the memory running at a higher speed.

Be sure to have ALL the memory timings and settings on Auto. Do this at least at first to get the memory running beyond 1333. Try 1600 first, and then move on to 1866, etc.

Memory speeds over 1600 are not a given with Sandy Bridge processors.