PCI-E bandwidth randomnly changing

[silvu]

Ok so since a few days ago i started noticing a little bit of stuttering in some games every now and then (Witcher 3 mostly) so i decided to reinstall my videocard drivers (with DDU) trying to fix this issue.

After doing that the problem persisted, but then i noticed something strange happening with my PCI-E bandwidth speed.

It is constantly and randomly changing from x2-x8-x16 (3.0) every time i restart or shutdown my PC.

And it will stay at that speed even when the GPU is being stressed by any 3D App, it only goes from let's say @ X2 1.1 TO X2 3.0 or x8 1.1 to x8 3.0.

This is the list of things that i tried until now to fix this issue:

- Upgraded and tried different driver versions.
- Flashed my MB BIOS with the latest update.
- Loaded "optimized defaults" on BIOS.
- Took out the card and cleaned the PCI-E lane and the card contact very carefully.
- As stated before, i updated my drivers to various versions (Adrenalin 18.2.1 - 18.4.1 -)
- Went to BIOS and changed PCI-E speed (Max Link Speed) to Auto - Gen1 - Gen2 - Gen3 every option available.

I don't know what else to try, i feel desperate by now.

Could it be the GPU is dying? my MB PCI-E lane could be faulty?

Hope someone can give me an insight of what could it be, thanks.

Specs


GIGABYTE Z170X Gaming 3 rev 1.0
Sapphire Nitro+ OC RX480 8GB
Intel Core i5 6600K
16GB Corsair Vengeance RAM @3200mhz
Corsair RM850x

 

[dextermat]

I think you narrowed it down pretty nicely.

The best thing to do would be to test a known working GPU to rule out the faulty one.
Could be you mobo having power delivery issues.

 

[silvu]

Yeah that's what i thought. Unfortunately, I don't have another GPU to test out.

But what i haven't tried yet is moving the card to the second PCI-E lane (x8) and see if the problem persists, if it does i think i can totally blame the GPU, and if not perhaps its just a faulty lane, which will be less problematic.

I will try to do that and reply again with the results.