Z170 GAMING K4 - RAMslots A1 and A2 not working

Tomaschewski wrote: Hello everybody, I've got an issue with the RAM slots on my mainboard. I have two 4GB HyperX Fury  DDR4-2133 modules, if I put them into the B1 and B2 slots, everything is working perfectly (in single channel mode, of course). But as soon as I put a RAM module into either A1 or A2, the system won't boot, not even beep, there's just the BIOS-LED flashing. I tried every possible combination and tried using only one RAM module. BIOS is updated to the newest version. Any help would be more than welcome! Tomaschewski

It sounds like you know both of your 4GB DIMMs are working, since they are both detected in the B channel, and you see a total of 8GB in the UEFI and in Windows, right?

If so, then for two 4GB DIMMs, they should be put in the A2 and B2 slots.

Give that a try, and while the PC is apart, clear the UEFI/CMOS. Then start the PC and check the memory detection.

If the PC won't start and the UEFI LED is flashing (I've never seen that), something is wrong.

Check if something is shorting the pins from the A channel DIMM slots on the underside of the board. Such as a mother board standoff that should not be there. Or the pins from the DIMM slots are bent and have shorted. I know that is a pain, but the PC not starting is a major, bad reaction.

Did you use the PC case you are using now for another PC? Did it use a different size board?

If a new PC case, were the mother board standoffs pre-installed?

You might have a short circuit elsewhere on the bottom of the board, but the A channel DIMM slots would be the primary place to look.

Otherwise, did you inspect the CPU socket for bent pins when you installed the CPU? I've never heard of bent pins in a CPU socket doing what you are experiencing, but who knows?