Question about PCI lanes

[Skywalker134]

I’m looking to add a WiFi 6 PCIe card to my PC, but I’m not sure if I’d have enough available PCI lanes. I have a feeling I’m already pulling available lanes from my graphics card, but I’m not 100% sure how it works exactly.

 

Motherboard: Asus Hero X

CPU: 8700k (16 lanes)

GPU: 3080 FTW3 (16x)

NVMe SSD: Samsung 960 EVO (4x)

Sound Card: Sound Blaster Z (1x)

 

 

 

[Electronics Wizardy]

The chipset has a good amount more lanes as its a pcie switch. The 16 lanes of the cpu will go to the gpu, and everything else will run off the chipsets pcie lanes.

[Skywalker134]

12 minutes ago, Electronics Wizardy said:

The chipset has a good amount more lanes as its a pcie switch. The 16 lanes of the cpu will go to the gpu, and everything else will run off the chipsets pcie lanes.

got it, so I should be able to run multiple 1x pci devices without affecting the GPU at all?

[Bismut]

1 minute ago, Skywalker134 said:

got it, so I should be able to run multiple 1x pci devices without affecting the GPU at all?

Should be the case, but you can always make sure by consulting your motherboards user manual. Keep in mind that all of the cards combined might bottleneck the chipset, but that seems unrealistic.

[brob]

1 minute ago, Skywalker134 said:

got it, so I should be able to run multiple 1x pci devices without affecting the GPU at all?

 

Yes, but it's motherboard dependent. Check the expansion slots section of the specifications web page. It will detail the expansion slots on the board and if they use CPU or chipset lanes.

[Skywalker134]

13 minutes ago, brob said:

 

Yes, but it's motherboard dependent. Check the expansion slots section of the specifications web page. It will detail the expansion slots on the board and if they use CPU or chipset lanes.

Thanks I'll check that out, I edited my original post to include the motherboard I have (Asus Hero X)

[Skywalker134]

15 minutes ago, brob said:

 

Yes, but it's motherboard dependent. Check the expansion slots section of the specifications web page. It will detail the expansion slots on the board and if they use CPU or chipset lanes.

Here's what the manual says for expansion slots:

 

Slot 1 - PCIe x1_1 slot

Slot 2 - PCIe x16/x8_1 slot

Slot 3 - PCIe x1_2 slot

Slot 4 - PCIe x8_2 slot

Slot 5 - PCIe x1_3 slot

Slot 6 - PCIe x4_3 slot

[brob]

21 minutes ago, Skywalker134 said:

Here's what the manual says for expansion slots:

 

Slot 1 - PCIe x1_1 slot

Slot 2 - PCIe x16/x8_1 slot

Slot 3 - PCIe x1_2 slot

Slot 4 - PCIe x8_2 slot

Slot 5 - PCIe x1_3 slot

Slot 6 - PCIe x4_3 slot

 

From page ix of the user manual, 2 X16 slots are provisioned from the CPU, four slots are provisioned from the chipset with some lane reallocation when particular slots are occupied.

 

 

If both of the CPU provisioned slots are occupied, each slot will get 8 lanes.