my CPU is a Intel i5 3570 IVY BRIDGE (ivybridge supports PCIE3.0)
now the problem is that when I put my VGA in the PCI Express 3.0 x16 slot (PCIE2: x16 mode), my monitor says: NO Signal When i put HD7870 in the other slot ( PCI Express 2.0 x16 slot (PCIE3: x4 mode) ) everything works fine...
Why I can't use the PCI3.0 x16?
PS: NOT a monitor/cable problem, tried with HDMI and DVI cable.
More aboutproblem asrock pro4 asus hd7870
Hi, Sometimes it's related to socket bent pins. Not sure though if it's your case.
How can i check if it's related to pins?
if it's a pin related issue, I have to send back my mobo to producer, right?
It depends. Sometimes they can be straightened. I would take the board outside the case and test again. If still the same, uninstall the CPU and use a magnifying glass or take a high resolution picture for inspecting the socket.