Some advice please on AMD B650E / X670E / X870E pcie lanes Sharing Lanes

[Wreckitangus]

Hi knowledgeable people. Not sure if this is best posted in the storage or motherboard forum, starting here under motherboard to see what comes back.

So 9800x3d is out and i want to upgrade on it. What i am getting confused about is with lane sharing on the motherboards with gpu and m.2 slots only found out tonight this is a thing .

So what i want is to be able to use full x16 lane for my GPU and at least 2x m.2 gen 5 without sharing lanes and slowing them down is this possible could anyone suggest a Motherboard that does this any suggestions wouldbe great thank you.

i did some more research i think i will go with ASRock X870E Nova Wifi for now

 

[Hankieroseman]

Good choice. Let us know how that turns out for you.

 

[TheLostSwede]

Hi knowledgeable people. Not sure if this is best posted in the storage or motherboard forum, starting here under motherboard to see what comes back.

So 9800x3d is out and i want to upgrade on it. What i am getting confused about is with lane sharing on the motherboards with gpu and m.2 slots only found out tonight this is a thing .

So what i want is to be able to use full x16 lane for my GPU and at least 2x m.2 gen 5 without sharing lanes and slowing them down is this possible could anyone suggest a Motherboard that does this any suggestions wouldbe great thank you.

i did some more research i think i will go with ASRock X870E Nova Wifi for now

You'll need an X670/E board to get two PCIe 5.0 M.2 slots and I don't think there even are a lot of boards that can do that.
The board you mentioned, doesn't do this, as the second set of PCIe 5.0 lanes from the CPU, are connected to the ASM4242 USB4 host controller.
No motherboard has more than two PCIe 5.0 M.2 slots unless you share with the x16 slot.

This might be of some help.

AMD AM5 Mobo DB

docs.google.com

AM5 Motherboards Sheet (X870/X670/B650/A620)

docs.google.com

 

[kapone32]

The Asus X670E E strix supports 4 5.0 M2 drives if you use a PCIe adapter card.

 

[Hankieroseman]

The Asus X670E E strix supports 4 5.0 M2 drives if you use a PCIe adapter card.

My X670E EXTREME board gets 240 FPS in DCS w/(see System Specs). Some people are saying...buttery-smooth...like some jazz music I can think of...So Good...
Feels So Good

 

[TheLostSwede]

The Asus X670E E strix supports 4 5.0 M2 drives if you use a PCIe adapter card.

It's still eating GPU lanes which is what the OP apparently didn't want.

 

[Shakallia]

On X870E the Asrock Nova and Taichi/Taichi Lite, and the MSI Godlike are the only ones that do not use lane sharing.

 

[Wreckitangus]

Yeah i went with ASRock X870E Nova Wifi got it from Slovakia of all places as sold out every where i am from the uk and it arrived here in 5 days

And as TheLostSwede said motherboards do not 2 m.2 gen 5 that will not share with gpu so i just settled for the one for now

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[Dr. Dro]

Yeah i went with ASRock X870E Nova Wifi got it from Slovakia of all places as sold out every where i am from the uk and it arrived here in 5 days

And as TheLostSwede said motherboards do not 2 m.2 gen 5 that will not share with gpu so i just settled for the one for now

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Great choice! I wish that the SSD capacity stagnation would end so we could purchase just one drive instead. But all in all, you won't be losing much if you stick to Gen 4 for a secondary SSD. There are some very competent and very nice Gen 4 drives out there. Upside, they also don't heat as much, so they'll probably be a tiny bit more reliable. Enjoy your new build!

 

[Wolverine2349]

It's still eating GPU lanes which is what the OP apparently didn't want.

I have that same board right now and probably gonna keep it depending on which direction I want to go. You can do 2 NVME Gen 3, 4, or 5 X4 direct to CPU without eating GPU lanes. You can add an additional 3rd NVME from chipset without eating any GPU lanes.

However, one of the slots does slice the GPU lanes in half. I have 3 NVME drives and avoid that slot.

So if you want 2 Gen 5 NVME X4 drives, the Asus X670E-E is a great option. Just make sure to not use NVME slot 3 which is what slices GPU lanes in half.

https://dlcdnets.asus.com/pub/ASUS/mb/Socket%20AM5/ROG_STRIX_X670E-E_GAMING_WIFI/E21210_ROG_STRIX_X670E-E_GAMING_WIFI_UM_V3_WEB.pdf?model=ROG%20STRIX%20X670E-E%20GAMING%20WIFI

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Now on X870E versions they are all like that and more than 1 NVME X4 to CPU slices GPU lanes in half because AMD's stupid mandatory USB 4 and mobo vendors siphons 4 CPU PCIe lanes on almost every board and no other options. Only exception is MSU X870E Godlike in which you can disable USB 4 Type C port or 2 on back and you get at least 2 Gen 5 X4 to CPU NVME lanes without touching the GPU.

I hate the X870E chipset as such.

The Asus X670E E strix supports 4 5.0 M2 drives if you use a PCIe adapter card.

You do not even have to use adpater card, but if you use all 4, GPU lanes are cut form 16 to 8. But if you use all 3 and leave M.2_3 empty, GPU lanes unaffected on topp slot as long as you use only top slot and put nothing in 2nd slot.

https://dlcdnets.asus.com/pub/ASUS/mb/Socket%20AM5/ROG_STRIX_X670E-E_GAMING_WIFI/E21210_ROG_STRIX_X670E-E_GAMING_WIFI_UM_V3_WEB.pdf?model=ROG%20STRIX%20X670E-E%20GAMING%20WIFI

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