Memory problems

[JL94x4]

My specs on my PC are as follows;

i7 7700K
Corsair DDR4 26.66mhz RAM 16GB
EVGA GTX 1080 SC 
Corsair 750M PSU

I overclocked my CPU to 4.8ghz and my ram to 2900mhz but got a boot failure, so I restored factory and rebooted into bios, saved and loaded Windows, however... black screen followed by 5 long beeps.

I unseated the CPU and there aren't any bent pins, CPU is seated correctly etc. So i turned my focus to Memory, I currently have 4x4GB and my ram slots are in the following order

DDR4_4 (Black)
DDR4_2 (Red)
DDR4_3 (Black)
DDR4_1 (Red)

So obviously running Dual mode would be all 4 running, or 2 in the same colour, so this is what I tried.

2 RAM in 4 and 3 and it doesn't post.
2 RAM in 2 and 1 and it doesn't post.
2 RAM in 4 and 2 and it doesn't post.
2 RAM in 3 and 1 and it posts and my windows boots however, its only running single channel.

I tested the other two sticks in the same slots, same order and get the exactly same result. 

Do you think its the Motherboard at fault, or CPU? I've kinda ruled out RAM as they all work in the 3 and 1 slots in Single channel. 

Could it be the CPU not allowing Dual Channel?

 

[mortino]

Definitely sounds like you burnt out something in the memory controller. Could be something on the board too between the CPU and the DIMM slots.

[JL94x4]

5 minutes ago, mortino said:

Definitely sounds like you burnt out something in the memory controller. Could be something on the board too between the CPU and the DIMM slots.

So you think its the CPU? Even though it boots with 2 RAM sticks in?

[mortino]

Just now, JL94x4 said:

So you think its the CPU? Even though it boots with 2 RAM sticks in?

I can't be sure ofc, that would require a CPU swap to test, how much voltage were you trying to push through the ram?

[JL94x4]

1 minute ago, mortino said:

I can't be sure ofc, that would require a CPU swap to test, how much voltage were you trying to push through the ram?

1.36v on RAM

1.26v on CPU

[mortino]

Just now, JL94x4 said:

1.36v

1.26v on CPU

Those are reasonable voltages. Check your motherboard manual for the beep code.

[JL94x4]

9 minutes ago, mortino said:

Those are reasonable voltages. Check your motherboard manual for the beep code.

The beep code is "CPU Error" however, my PC is currently booted with 8GB RAM in single channel, with them in Black (3) and Red (1) DIMM slots. Surely a CPU Error wouldn't boot at all?

[mortino]

Just now, JL94x4 said:

The beep code is "CPU Error" however, my PC is currently booted with 8GB RAM in single channel, with them in Black (3) and Red (1) DIMM slots. Surely a CPU Error wouldn't boot at all?

Well if the error only happens when you are using that part of the memory controller on the CPU. Or do you get the beep code even when you boot using 2 dimms?

[JL94x4]

Just now, mortino said:

Well if the error only happens when you are using that part of the memory controller on the CPU. Or do you get the beep code even when you boot using 2 dimms?

I only get the 5 beeps when using the 4 and 2 slots, as soon as i move them RAM to 3 and 1 it boots fine, used AIDA64 and stressed without issues. I only get the error and no post on the first two slots on the board.