Question Is PCI-E 5.0 backward Compatable

[Knight-Eagle]

Have a ASUS 790 MotherBoard PCI-E5.0 problems
Bought an ASUS 790ZX motherboard. And the video card was the RX580 8G GDDR5 (3.0) installed in the first PCI-E slot (5.0) next to the CPU. First off wouldn't boot up. took it in to the shop where the tech figured the board might be bad. He placed his card in the top slot next to the cpu slot still wouldn't work, tryed the bottom PCI-E slot and it worked fine. As for dropping my RX580 (3.0) card into the bottom slot there no room because of the power supply and case wiring. Sent the board in after getting another vidio (3.0) card placed it in the bottom slot started up worked fine Forgot to try it in the upper slot below the CPU. Now I was in contact with Asus and they told me that PCI-e (5.0) was not Compable with RX 580 (3.0) pci-e What can I do? or is there a fix besides pay over 2k for a 5.0 card

Ok been out of building computers and forums for a spell long spell;

1) CPU I7/14700f
2) Asus 790ZX with wifi PCI-E 5.0 / PCI-E 3.0
3) CPU AIr Cooler AMD AM5/AM4/AM3 series
4) ssd-2t // sata 12tb HHD
5) RX 580 8G GDDR5 vidio card Pci-E3.0
6) OS-win10 (3yrs upgrade from 7)
7) ? gpu ?
8) 850w Power supply is that Psu?
9) ram 128MB

most of the parts are less than 3 months old

Case new for new boards

As for version of bios currient for Asus which they are upgrading since they have the board now.

 

[Lutfij]

Welcome to the forums, newcomer!

To answer your thread title's question, Yes.

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.