OMG
Dell has lied to me!
I have opened my Dimension 8200 and at my surprise I can read RTL8139 on the NIC cpu
Arghhhhhhhhh when it is written on my mom customer command that the NIC is a Cnet200WL Fast Ethernet Card
I don't know the respective prices but it's bad from Dell
All other devices are the official ones at least...
And it explains why my system didn't detect anything else
Thx for the suggestion
BTW i have cleaned my air conditionned inside lol
it was full of dust
You won't believe me but now my computer makes hardly no noise
I hope they still work lol
we will see