Stick of ram causing both the neighboring slots and itself to be undetected

[kovame7235]

cpu: threadripper 1950x

motherboard: taichi x399

ram: x8 corsair vengeace 4gb (all ram sticks are the same)

 

I have a ram stick that disables itself and the neighboring slot. Wherever I put that ram stick, it has the same effect on the neighboring slot. When I don't plug it in, the neighboring slot works. I've also tried swapping the two sticks but it doesn't make a difference.

What I don't understand is that if the stick's dead, why would it disable the neighboring slot instead of the slot it's linked to?

If the bad stick is in D2, shouldn't it disable C2 instead of D1?

Ram configuration:

D2 D1 C2 C1 A1 A2 B1 B2

 

Exhibit A (lower case is the defective's ram location):

d2 D1 C2 C1 A1 A2 B1 B2

Result: D2 and D1 not recognized.

 

Exhibit B (lower case is the defective's ram location):

D2 D1 C2 c1 A1 A2 B1 B2

Result: C2 and C1 not recognized.

 

Exhibit c (lower case is the defective's ram location):

D2 D1 C2 C1 A1 A2 B1 b2

Result: B1 and B2 not recognized.

 

[.Apex.]

18 minutes ago, kovame7235 said:

Exhibit A (lower case is the defective's ram location):

d2 D1 C2 C1 A1 A2 B1 B2

Result: D2 and D1 not recognized.

 

Exhibit B (lower case is the defective's ram location):

D2 D1 C2 c1 A1 A2 B1 B2

Result: C2 and C1 not recognized.

 

Exhibit c (lower case is the defective's ram location):

D2 D1 C2 C1 A1 A2 B1 b2

Result: B1 and B2 not recognized.

RAM Channels are distinguished by the letter, so A1 and A2 are both on the same channel, so if a bad stick is inserted in one of them it would disable the other slot (same channel) since they are both connected together on the traces of the motherboard

[BobVonBob]

This is the expected behavior, each of the letters is for an individual memory channel, and each channel can have two sticks of RAM. The reason you are supposed to pair sticks in separate lettered slots like the manual suggests is because they aren't linked, so they can be addressed separately by the CPU.

[.Apex.]

I see the confusion now, the manual suggests that each alternating RAM Slot is "linked together" but that's not the case, they do that to instruct you how to pair the RAM sticks, as in to achieve Dual Channel or Quad Channel then there has to be a RAM stick in each of those channels, putting 2 RAM sticks in the same channel would still be Single Channel

 

[kovame7235]

Thank you very much for the well written explanation, I really appreciate it. It makes much more sense now

I'm very sorry to have bothered you guys with such a trivial question. Once again the issue is between the computer and the chair!