Question Adding a USB PCIe card makes my GPU go to 4x from 16x

Toggle sidebar Toggle sidebar
D

darge82

Reputable
Jan 27, 2019
28
1
4,545
I have an Asus TUF Z690 Wifi D4 motherboard and a 12700k. I run an EVGA 3090 in the X16 Gen 5 slot(top most slot). All has been working well. I am trying to add a USB 3.0 PCIe expansion card to the PC, it is SATA powered. When the USB expansion card is connected. It drops the GPU lane down to 4x and the USB card is not detected. Once the USB PCIe card is removed, the GPU slot goes back to x16. I do also have an M2 NVME 2TB SSD connected to the M2_1 slot. Am I using too many lanes on the PCIe or do I need to change a configuration in the BIOS. Right now all PCIe settings are set to AUTO. Using a different PCIe slot is not an option due to the 3090 blocks the rest of them.

EDIT Now that I looked into it more, my GPU is at 4x even with it disconnected, it looks like it has been 4X since I built this PC. Its showing the M2_1 and x16 Gen5 lanes as 4x in BIOS and GPU Z and Nvidia COntrol panel confirm it. My 3090 benches where it has since I built it with a 20,000 score on Timespy. I am confused on what has happened here.
 
Last edited:
Sort by date Sort by votes
Update on why my GPU was showing 4x. I had to remove the GPU to get the USB PCIe card in. For some reason it was making a poor connection. Reseated it and the GPU is showing 16x now, M2 SSD is showing 4x and USB PCie card is showing 2x but windows is not detecting it. It is a StartechPCIe USB expansion card, their site states it is a 4x. Since its showing up as 2x in the BIOS is this the reason its not being detected?
 
Upvote 0 Downvote
darge82 said:
I have an Asus TUF Z690 Wifi D4 motherboard and a 12700k. I run an EVGA 3090 in the X16 Gen 5 slot(top most slot). All has been working well. I am trying to add a USB 3.0 PCIe expansion card to the PC, it is SATA powered. When the USB expansion card is connected. It drops the GPU lane down to 4x and the USB card is not detected. Once the USB PCIe card is removed, the GPU slot goes back to x16. I do also have an M2 NVME 2TB SSD connected to the M2_1 slot. Am I using too many lanes on the PCIe or do I need to change a configuration in the BIOS. Right now all PCIe settings are set to AUTO. Using a different PCIe slot is not an option due to the 3090 blocks the rest of them.

EDIT Now that I looked into it more, my GPU is at 4x even with it disconnected, it looks like it has been 4X since I built this PC. Its showing the M2_1 and x16 Gen5 lanes as 4x in BIOS and GPU Z and Nvidia COntrol panel confirm it. My 3090 benches where it has since I built it with a 20,000 score on Timespy. I am confused on what has happened here.
Click to expand...
Which slot are you using for the usb card? The chart on page 1-7 of the manual seems to imply that if you stick anything in the 5th slot at the bottom of the motherboard that will reduce the gpu to 4x. Can you not use slots 3 or 4? Did you download the drivers and install them?

https://www.startech.com/en-us/cards-adapters/pexusb3s44v

%20USB%203.0%20Controller%20Card.zip]https://sgcdn.startech.com/005329/media/sets/Renesas-uPD72020x_Drivers/[Renesas_uPD720201_2]%20USB%203.0%20Controller%20Card.zip

There's also a firmware update but you'll have to figure out what version you already have.
 
Upvote 0 Downvote
dwd999 said:
Which slot are you using for the usb card? The chart on page 1-7 of the manual seems to imply that if you stick anything in the 5th slot at the bottom of the motherboard that will reduce the gpu to 4x. Can you not use slots 3 or 4? Did you download the drivers and install them?

https://www.startech.com/en-us/cards-adapters/pexusb3s44v

%20USB%203.0%20Controller%20Card.zip]https://sgcdn.startech.com/005329/media/sets/Renesas-uPD72020x_Drivers/[Renesas_uPD720201_2]%20USB%203.0%20Controller%20Card.zip

There's also a firmware update but you'll have to figure out what version you already have.
Click to expand...

I replied above your comment with an update. The GPU needed to be reseated and that fixed it from being at 4x and went to 16x. The GPU now is @ 16x and the SSD @ 4x. However, with the Startech plugged in, its showing 2x on the Startech in the BIOS and GPU remains at 16x now. My only option is to install the USB card to the most bottom PCIe 16x slot due to the GPU (EVGA 3090 FTW3 Ultra) blocks all other slots on the motherboard. The only other slot that is not blocked by the GPU is a PCie 1x slot, but the USB card is a 4x.

I cannot install drivers or firmware as when I do with the Startech drivers it states "device not detected" The USB card does not show in Device manager at all. BIOS knows a device is plugged into that slot as its showing it at 2x, but windows is not detecting the USB card.
 
Last edited:
Upvote 0 Downvote
darge82 said:
I replied above your comment with an update. The GPU needed to be reseated and that fixed it from being at 4x and went to 16x. The GPU now is @ 16x and the SSD @ 4x. However, with the Startech plugged in, its showing 2x on the Startech in the BIOS and GPU remains at 16x now. My only option is to install the USB card to the most bottom PCIe 16x slot due to the GPU (EVGA 3090 FTW3 Ultra) blocks all other slots on the motherboard. The only other slot that is not blocked by the GPU is a PCie 2x slot, but the USB card is a 4x.

I cannot install drivers or firmware as when I do with the Startech drivers it states "device not detected" The USB card does not show in Device manager at all. BIOS knows a device is plugged into that slot as its showing it at 2x, but windows is not detecting the USB card.
Click to expand...
I seem to be missing something here. The EVGA blocks slots 1 and 2. Can the usb card not be placed in the 4x slot 3?
 
Upvote 0 Downvote
You must log in or register to reply here.

TRENDING THREADS

Latest posts

Moderators online

Share this page

COMPANY
RESOURCES
FOLLOW
Top Bottom