@smellsofbikes no clue, don't know how lenovo diagnostics works and newer passmark memtest 10.2 did a full pass without errors
memtest86+ 5.01 freezes on test 1 54% and i've seen it freeze at exactly the same point (just a couple of seconds in really) on another hardware entirely, which is what made me try another memtest
and yes this was memtest from two different liveusbs, which both had 86+ 5.01 exactly