господа, сомневаюсь насчет порядка микросхем памяти, на этой плате у которой микросхема спереди и сзади

When each memory chip does NOT have another chip EXACTLY on the other side - it works in typical 32-lane mode, not the 16-lane mode.

So, I think the exact soldering orientation does not matter. Modules on different sides may have dirrerent value for their Mirror Function pin, but for the GPU there is no difference on which side the Memory IC is soldered.

M1, M506 - channel A (32-63, 0-31)
M8, M503 - channel B (32-63, 0-31)
M6, M501 - channel C (32-63, 0-31)
M4, M507 - channel D (32-63, 0-31)