RX 5700XT Using PCIe x2 Instead of X16

[Thermopylae_480]

I'm running a MSI RX700XT in the main PCIe x16 Slot and have no cards in the auxiliary PCIe x16 or any other PCIe slot. I am also not using the M.2 slot. However, GPU-Z, CPU-Z and AMD Adrenaline all report the lane width for the card as x2 even when under load. All drivers and BIOS are up to date for the motherboard and video card. I've tried cleaning and re-seating the video card as well as re-seating the processor. Both 8-pin power connectors are plugged in and on separate rails. As I was writing this I realized I hadn't really bench marked to see if it really even mattered, and apparently it doesn't as my 3DMark Steal Nomad score (2123) looks to be where it should be. Still, I find it curious. Attached are outputs from GPU-Z and CPU-Z. Thoughts anyone?

• MSI Z170M Mortar Motherboard
• Evga 850 Watt PSU
• Intel i5 6600K CPU
• SATA Drives Qty. 4

 

[ShrimpBrime]

Well might be able to manually set the Pcie lanes in the system bios settings. Have you looked there? Does it say in the manual anything about m2? Does the board simply need a bios update?

 

[basco]

did ya just update the driver or was it before too ?

 

[Splinterdog]

I have the same card and it reads x8 in a x16 slot. Both my .M2 slots are used, so I don't know if that makes any difference, however the card works flawlessly, touch wood.

 

[basco]

what shrimp said try to set pci-e to 3.0 or test other benchmarks because if its really at x2-3.0 you should score a lot lower

 

[Deleted member 234478]

touch wood.

careful you dont get a splinter touching that wood

 

[VuurVOS]

I'm running a MSI RX700XT in the main PCIe x16 Slot and have no cards in the auxiliary PCIe x16 or any other PCIe slot. I am also not using the M.2 slot. However, GPU-Z, CPU-Z and AMD Adrenaline all report the lane width for the card as x2 even when under load. All drivers and BIOS are up to date for the motherboard and video card. I've tried cleaning and re-seating the video card as well as re-seating the processor. Both 8-pin power connectors are plugged in and on separate rails. As I was writing this I realized I hadn't really bench marked to see if it really even mattered, and apparently it doesn't as my 3DMark Steal Nomad score (2123) looks to be where it should be. Still, I find it curious. Attached are outputs from GPU-Z and CPU-Z. Thoughts anyone?

• MSI Z170M Mortar Motherboard
• Evga 850 Watt PSU
• Intel i5 6600K CPU
• SATA Drives Qty. 4

Did you consider that it could be a power saving feature which is lowering the PCI-E link speed and width to lower levels when idle?

 

[Thermopylae_480]

Well might be able to manually set the Pcie lanes in the system bios settings. Have you looked there? Does it say in the manual anything about m2? Does the board simply need a bios update?

Unfortunately, I can't specify the lane count, but I did try changing it from Auto to PCIe 3.0. In my initial post I stated the BIOS was up to date as are all drivers. I looked briefly for a firmware update for the card, but didn't see any. Doesn't mean I didn't miss something though.

did ya just update the driver or was it before too ?

Yeah, but it was doing it before too. I'm not sure how long either since checking the lane count isn't normally anything I think about.

Did you consider that it could be a power saving feature which is lowering the PCI-E link speed and width to lower levels when idle?

I did, that's why I said I tested it under load. CPU-Z, GPU-Z, and AMD Adrenaline never registered a change.

 

[ShrimpBrime]

Is it the card? Try it in another system.

Is it the board? Try a different card in the current system.

Is possible the only approach at this point.

 

[eidairaman1]

Pcie lanes allowed, dependent on mobo ofc

Intel® Core™ i5-6600 Processor (6M Cache, up to 3.90 GHz) - Product Specifications | Intel

Intel® Core™ i5-6600 Processor (6M Cache, up to 3.90 GHz) quick reference with specifications, features, and technologies.

ark.intel.com

Get your manual from here:

https://www.msi.com/Motherboard/Z170M-MORTAR/support#manual

Is it the card? Try it in another system.

Is it the board? Try a different card in the current system.

Is possible the only approach at this point.

Page 28 of his manual, if anything for troubleshooting I'd only have the 5700 installed in the top pcie 16x slot

 

[Thermopylae_480]

Is it the card? Try it in another system.

Is it the board? Try a different card in the current system.

Is possible the only approach at this point.

Yeah, I suspect you are right. I tried and older GeForce 1060, but it wouldn't POST. Don't even know if that card works anymore. The 5700XT won't fit in my media center PC unfortunately. The processor and motherboard are almost 10 years old. So screw it, time for an upgrade. Ordered a Ryzen 9 7950X, ASUS Prime X670E-PRO, and other stuff. We'll see what happens when it gets plugged in with those.

 

[ShrimpBrime]

Yeah, I suspect you are right. I tried and older GeForce 1060, but it wouldn't POST. Don't even know if that card works anymore. The 5700XT won't fit in my media center PC unfortunately. The processor and motherboard are almost 10 years old. So screw it, time for an upgrade. Ordered a Ryzen 9 7950X, ASUS Prime X670E-PRO, and other stuff. We'll see what happens when it gets plugged in with those.

Comes in with..
F it, I'll just order a 7950X.

Love it.

 

[eidairaman1]

Comes in with..
F it, I'll just order a 7950X.

Love it.

Pcie slot 4 becomes 2x when pcie slot 3 is occupied. Pcie slot 1 is 16x, pcie slot 4 is 4x when nothing is in pcie slot 3.

The only other way a gpu doesnt see full bus speed is if a smd part by the pcie blade is damaged/ko'ed

 

[ShrimpBrime]

Pcie slot 4 becomes 2x when pcie slot 3 is occupied. Pcie slot 1 is 16x, pcie slot 4 is 4x when nothing is in pcie slot 3.

The only other way a gpu doesnt see full bus speed is if a smd part by the pcie blade is damaged/ko'ed

Or it's stuck in some lower power state for whatever reason.

 

[eidairaman1]

Or it's stuck in some lower power state for whatever reason.

Yeah Windows 10/11 can do that.

 

[Outback Bronze]

Yeah Windows 10/11 can do that.

Yep, it surely does.

My card just stepped down to PCI-E 1.1 but kept its 16x. Trying to remember if I've seen it clock down the 16x bus to 8x or 4x etc.

 

[agent_x007]

PCI-e lanes dropping in idle are laptop only feature IIRC. Desktop cards (well, aside from entry tier ones), are always x16.
I would test CPU on another system, or MB with different CPU (if you don't have other cards that boot).
There is a chance your CPU and/or MB are simply damaged (I assume pins in CPU socket are OK).

 

[basco]

@Outback Bronze and your scores\fps are normal so then it´s just a reading error or windows thingy ?
thy for the reply

 

[eidairaman1]

PCI-e lanes dropping in idle are laptop only feature IIRC. Desktop cards (well, aside from entry tier ones), are always x16.
I would test CPU on another system, or MB with different CPU (if you don't have other cards that boot).
There is a chance your CPU and/or MB are simply damaged (I assume pins in CPU socket are OK).

No, its a default thing in windows,

Yep, it surely does.

My card just stepped down to PCI-E 1.1 but kept its 16x. Trying to remember if I've seen it clock down the 16x bus to 8x or 4x etc.

View attachment 354312View attachment 354313

My rig does the same when idle, under load it maxes out, it's a power save function

 

[Outback Bronze]

your scores\fps are normal

Yep, perfectly fine. I was just showing an example of when the PCIe is under load then idle.

it's a power save function

Yes, example was given for that exact reason