# GPU-Z PCIe reporting speed bug?



## Cyphadeaus (Feb 7, 2021)

When I open GPU-Z as you see below it reports the PCIe link speed as 3.0 when the PC is showing it running at 4.0 in the device properties. Is this a known bug? 

An as the "tool tip" says to run a load; the reporting never changes btw.


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## Naki (Feb 7, 2021)

Which motherboard is this on?
What CPU?


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## evernessince (Feb 7, 2021)

Cyphadeaus said:


> When I open GPU-Z as you see below it reports the PCIe link speed as 3.0 when the PC is showing it running at 4.0 in the device properties. Is this a known bug?
> 
> An as the "tool tip" says to run a load; the reporting never changes btw.
> 
> View attachment 187394



That value doesn't represent PCIe link speed.  For example, I have my 1080 Ti in a PCIe x16 and it shows 00000001.

The reading from GPU-Z is likely accurate.  Of course you can always double check in your BIOS.


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## Cyphadeaus (Feb 7, 2021)

Naki said:


> Which motherboard is this on?
> What CPU?


MSI X570 Pro Carbon Wifi
3700x


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## W1zzard (Feb 7, 2021)

AMD has a PCIe bridge inside the GPU now, so it's no longer

GPU <-> CPU, but GPU <-> Bridge <-> CPU

Check in device manager, the bridge is running in Gen 3 mode, so your overall bandwidth is Gen 3 not Gen 4

Please c onfirm


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## Cyphadeaus (Feb 7, 2021)

> evernessince said:
> 
> 
> > That value doesn't represent PCIe link speed.  For example, I have my 1080 Ti in a PCIe x16 and it shows 00000001.
> ...





W1zzard said:


> AMD has a PCIe bridge inside the GPU now, so it's no longer
> 
> GPU <-> CPU, but GPU <-> Bridge <-> CPU
> 
> ...


W1zzard,

I'm not sure where you are referring too. Didn't see any bridge settings under the 6800 XT, or am I supposed to looking under the system devices? Need a little more info from you thanks.

PS:  set all PCIe settings in the bios to GEN 4 since I'm running all gen 4 devices, (mobo, gpu, M.2's). Checked in GPU-z still says 3.0.


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## W1zzard (Feb 7, 2021)

Device Manager, View devices by connection. This should help you figure out the path from the GPU to the CPU.

Are they all running in Gen 4 mode?


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## Cyphadeaus (Feb 8, 2021)

W1zzard said:


> Device Manager, View devices by connection. This should help you figure out the path from the GPU to the CPU.
> 
> Are they all running in Gen 4 mode?


The ones I did find said PCIe connection speed 000004. But I don't trust those after making manual changes and they didn't report correctly when dropping the link speed.


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