Question rx vega 56 works only on pcie2.0 (not 3.0)

[bichedeflex]

hey guys , i ask your wisdom here
my rx vega 56 ( rog strix ) is not recognised on pcie 3.0 setup , it turns on , lights and fans , but not detected through bios hardware or anything

when plugged to a system on pcie 2.0 port 4x , it works very fine ((and draws a lot of power btw)
( furmark) (amd system)
but on my recent build intel i9 pcie 3.0 , system boots but no show for the vega .. ( tried tweaking bios for pcie 2.0 but no options

gpu bios is locked , updated it , dowgraded it , nothing does improve

gpu is in super condition
only thing that could bother is this little mark on a lanes ( lanes have all been tested with multimeter)


im guessing that cpu (in charge of pcie 3.0 )

any ideas welcome , cant understand the prob , and asus CS are not supportive at all , nore would i recommend them , this card if im right with serial number is from 2018 .. but out of warranty
..

any ideas ?

 

[rgd1101]

full system spec? include brand and model of the psu

 

[bichedeflex]

psu antec 850
z490 aurus ultra ( neither pcie ports ) unable to select pcie 2.0 via neithet bios's
i9-10850k
rtx 3070 ( in or out, plugged or not)
32gb ddr4


works fine on i5-4xxx pcie 2.0 4x port
amd fx pcie 2.0 4x port
here is furmark
i got a specialist on it , unable to find the prob

 

[bichedeflex]

psu antec 850
z490 aurus ultra ( neither pcie ports ) unable to select pcie 2.0 via neithet bios's
i9-10850k
rtx 3070 ( in or out, plugged or not)
32gb ddr4


works fine on i5-4xxx pcie 2.0 4x port
amd fx pcie 2.0 4x port
here is furmark
i got a specialist on it , unable to find the prob

brand new antec gold hcg ( tier a if im right) 850w , impressive quality on tests

 

[spentshells]

Okay weird, what about gpu bios? Is it running the correct version?
Sounds like mining bios to me.

 

[bichedeflex]

gpu bios is locked, been updated and downgraded , nothing does .. not sure how it could have been replaced by mining bios