MPG Z390 GAMING EDGE AC - PCIE running at x8 instead of x16

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Hello,

My 1080 is in the pcie x16 slot but the bios and CPU-Z both report that it is running at x8. Because I am an idiot and lost the CPU protector, I accept that an RMA is unlikely. I have reseated the card and the CPU but the problem remains.

I inspected the CPU socket but couldn't see any bent pins (I have read that this is one likely explanation) but I can't rule out that I simply haven't seen them (my eyes aren't that good).

Before I replace this piece of junk with another one at my own expense, are there any other likely points of failure (e.g. the 9700K itself?) that might cause this? I don't want to go through the trouble of buying a replacement board only to discover the same problem.
 

Svet

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Have you put load on the GPU before check for the lines?
 
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Hello,
Yes I tried that but it made no difference to what GPU-Z reported (I think the only thing that changed is that it went from x8 1.1 to x8 3.0). I thought maybe it was a power saving function but apparently this is not how the power saving feature is implemented and it should read x16 in single card mode with no other devices occupying the other slots / M.2 SSD installed.
 

Topo

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Have you installed the graphics card in the first PCIe slot (The one closest to the CPU) because thats a dedicated 16x PCIe slot?
There should also be a setting in the bios PEG X - Max Link Speed [Auto]. Make sure its on "Auto" or try putting it on "Gen.3".
 
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Hello,
Yes the GTX 1080 (not Ti) is in the first PCI-E slot closest to the CPU. I have the settings of PEG 0 and PEG 1; both are currently set to Auto. I have set both to Gen 3, rebooted and checked the BIOS and GPU-Z. No change to the link speed.
 

Topo

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Have you updated to the latest bios?
Also it could be an NVIDIA driver problem. Uninstall your current driver, use DDU to clear any reminants in safe mode. Then install the latest NVIDIA driver and check again. Do the little render test in GPU-Z and see if it changes under load.
 
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Hello,
Bios updated to the latest June version (tried downgrading too but that didn't change it). Latest drivers updated and DDU was used to clear out the old garbage in safe mode. Render test changed from x8 1.1 to x8 3.0 (as it always does).
 

Topo

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Check Windows Power Option - Advanced Power Options - PCI Express - Link State Power Management. Default is Moderate power saving or change it to off and restart.
Also power off take off the graphics card check the pins on the connector for any damage and clean them with contact cleaner and install the card again. Make sure its seated properly. Also make sure the pcie power cords are connected properly.
If that doesn't make a difference then try with a different graphics card even any old 16x card if you can.
 
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Hello,

PCI Express Link State options changed to "off" and restarted; no change. No damage to card pins but cleaned anyway and power cables fully seated; no change. Tried with an old 750ti I had lying about; no change.

If I were to guess, it is either the board that is broken/faulty (why, I'm not sure) or the 9700K is.

Buy a new board and then re-test?
 

Topo

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Yes we know now its not the GPU!
Is this a new build or just started to happen?
Fresh install of Windows?
What make you suspect in the CPU?
 
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Hello,

Some threads I have read (not on here) suggest that the problem has been corrected by replacing the CPU. It is a new-ish build that I threw together as a quick and dirty upgrade from a 6600K in March.

No significant problems with it except this and it is doing my head in. Could have been worse for first build and I know that this issue has negligible impact on gaming performance but I am more concerned about the next generation of cards and whether this issue could cause saturation and performance degradation. Rather resolve it before throwing money at a new GFX card.
 
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Topo

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You should make a fresh install of Windows so you wont have any conflict with old motherboard drivers. It could be the reason why its stuck on 8x!
Also just check these settings in the Bios are set to default.
PEG X - Max Link Speed [Auto]
Initiate Graphic Adapter [PEG]
IGD Multi-Monitor [Disabled]
Download and install the Intel Chipset Driver from motherboard support website here:
https://www.msi.com/Motherboard/support/MPG-Z390-GAMING-EDGE-AC#down-driver&Win10 64
Just to make sure you done everything possible.
 
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You should make a fresh install of Windows so you wont have any conflict with old motherboard drivers. It could be the reason why its stuck on 8x!
Also just check these settings in the Bios are set to default.
PEG X - Max Link Speed [Auto]
Initiate Graphic Adapter [PEG]
IGD Multi-Monitor [Disabled]
Download and install the Intel Chipset Driver from motherboard support website here:
https://www.msi.com/Motherboard/support/MPG-Z390-GAMING-EDGE-AC#down-driver&Win10 64
Just to make sure you done everything possible.
Yes it was a fresh install of windows after the upgrade was done (new license and so on). The problem is that the BIOS is showing x8 in the board explorer, so I am not sure whether OS or software conflicts would make a difference if the problem persists in BIOS.

PEG X (I assume X is a substitute for PEG 0 or 1?) has been set to Gen 3 and Auto and does not appear to any change the x8 to x16 in BIOS or GPU-Z. Initiate Graphic Adapter has always been set to PEG and IGD Multi-Monitor has always been disabled.
 

Topo

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I guess there is nothing else that can be done :wall: I hereby declare a faulty motherboard! Prepare the crusher....:smash:
This seems like a recent board why don't you RMA it?
 
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I guess there is nothing else that can be done :wall: I hereby declare a faulty motherboard! Prepare the crusher....:smash:
This seems like a recent board why don't you RMA it?
I would but I lost the CPU socket protector. Only got myself to blame for that one.

I'll replace it later in the month.
 

plutomate

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not sure if i miss anything, but you only have 1 PCIe device (VGA) right. If you put 2 devices at the same time, the bandwidth is gonna drop to x8.
 
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not sure if i miss anything, but you only have 1 PCIe device (VGA) right. If you put 2 devices at the same time, the bandwidth is gonna drop to x8.
Hello,
Indeed but there is only one device occupying any of the PCIe slots and that is the GPU itself; it should not be running in x8 mode in this configuration. For some reason the GPU is not using all of the available lanes and it is either the board or CPU that is to blame (as I see it anyway). I doubt that Intel will RMA the CPU until the board is ruled out and I don't have another compatible processor to test this with, so easier to replace the board.
 

plutomate

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then i see no other reason for the bandwidth drop unless it's faulty hardware, hope RMA can fix your problem :biggthumbsup:
 
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then i see no other reason for the bandwidth drop unless it's faulty hardware, hope RMA can fix your problem :biggthumbsup:
Ah no, that wouldn't happen because I lost the CPU socket protector. Inspecting the new and old board, I think one of the socket pins was bent as the replacement motherboard now correctly reports x16.

Let this be a lesson kids, give the CPU a little wiggle in the socket to make sure it is sitting right before lowering the lever and don't lose that seemingly worthless bit of plastic cpu socket protector.

All in all, a rubbish first CPU/mobo upgrade experience but I am now content.
 
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