PC won't boot in dual channel slots but will in any other slot combination.

[r1cky-]

So, my friend's PC which is about 1 month old has got a problem recently, it won't boot if the RAM sticks are installed in B1 B2, the dual channel slot configuration, but will in any other slot configuration (A1 B1 for example). We even tried my ram sticks which are pretty much the same (his had the AMD expo profile, mine had the normal XMP), but nothing changed. Where can the problem be from?

This is his configuration:
i5-14600kf
Corsair vengeance RAM 32gb 6000mhz CL36
1080ti strix

[Agall]

10 minutes ago, r1cky- said:

So, my friend's PC which is about 1 month old has got a problem recently, it won't boot if the RAM sticks are installed in B1 B2, the dual channel slot configuration, but will in any other slot configuration (A1 B1 for example). We even tried my ram sticks which are pretty much the same (his had the AMD expo profile, mine had the normal XMP), but nothing changed. Where can the problem be from?

This is his configuration:
i5-14600kf
Corsair vengeance RAM 32gb 6000mhz CL36
1080ti strix

Usually A2 B2 is the optimal two DIMM configuration, since that's memory controller A and B's primary slot. That's usually slots 2,4 relative to the CPU socket. Its usually silk screened nearby the DIMM slots on the motherboard, like this on the B760 Asus Strix-F.

 

[FI Fheonix]

1 hour ago, r1cky- said:

So, my friend's PC which is about 1 month old has got a problem recently, it won't boot if the RAM sticks are installed in B1 B2, the dual channel slot configuration, but will in any other slot configuration (A1 B1 for example). We even tried my ram sticks which are pretty much the same (his had the AMD expo profile, mine had the normal XMP), but nothing changed. Where can the problem be from?

This is his configuration:
i5-14600kf
Corsair vengeance RAM 32gb 6000mhz CL36
1080ti strix

Could be a motherboard problem, Is there anything visible obstructing the dimm? 

[Nena Trinity]

Mine had weird issues after a BIOS update, I had 4 sticks built up by 2 kits and for some reason post update dimm 1 & 2 gotta have slowest kit and 3 & 4 gotta have the faster kit. Before they were set like it SHOULD BE! I suspect it could be the BIOS version?