X870E PCIE Sharing with Multiple M.2 Drives

[shazz357]

Hey guys, so a lot of X870e motherboards now have PCIE lane sharing with the x16 slot whenever you install multiple M.2 drives. I specifically have an Aorus Pro Ice and the manual states that the x16 slot will run at x8 if drives are installed in the 2nd and 3rd spots. Those slots do say that they are pcie gen 5 compatible so I assume the x16 slot will operate at pcie gen 5 x8 given the GPU is also a pcie gen 5 card, right? Pcie gen 4 x8 from what I've seen is about when RTX 4080 and above cards begin to become affected by the loss of bandwidth so just wanted to ask around if anyone knows for sure that the lane sharing situation sets the x16 slot to gen 5 and not gen 4. 

[Blue4130]

3 minutes ago, shazz357 said:

Hey guys, so a lot of X870e motherboards now have PCIE lane sharing with the x16 slot whenever you install multiple M.2 drives. I specifically have an Aorus Pro Ice and the manual states that the x16 slot will run at x8 if drives are installed in the 2nd and 3rd spots. Those slots do say that they are pcie gen 5 compatible so I assume the x16 slot will operate at pcie gen 5 x8 given the GPU is also a pcie gen 5 card, right? Pcie gen 4 x8 from what I've seen is about when RTX 4080 and above cards begin to become affected by the loss of bandwidth so just wanted to ask around if anyone knows for sure that the lane sharing situation sets the x16 slot to gen 5 and not gen 4. 

Yes the x16 slot is pcie 5.0

[Tridefender]

54 minutes ago, shazz357 said:

the lane sharing situation sets the x16 slot to gen 5 and not gen 4. 

It will be clipped to x8 regareless of gen 5 or gen 4. Your motherboard supposedly don't have a plx chip to "expand" lanes available by breaking up gen5 lanes to twice the amount of gen4 lanes

 

Infact the performance loss would be small, you need not worry.

[Blue4130]

7 minutes ago, Tridefender said:

It will be clipped to x8 regareless of gen 5 or gen 4. Your motherboard supposedly don't have a plx chip to "expand" lanes available by breaking up gen5 lanes to twice the amount of gen4 lanes

 

Infact the performance loss would be small, you need not worry.

PLX chips haven't been a thing on consumer motherboards for over a decade.  I doubt they are even on server boards these days.

[Tridefender]

4 minutes ago, Blue4130 said:

PLX chips haven't been a thing on consumer motherboards for over a decade.  I doubt they are even on server boards these days.

although I would love to have one lol, 4060ti + itx motherboard = 8 pcie lanes lost 

[Blue4130]

4 minutes ago, Tridefender said:

although I would love to have one lol, 4060ti + itx motherboard = 8 pcie lanes lost 

https://www.techpowerup.com/review/asus-geforce-rtx-4060-ti-dual-with-m-2-slot/#:~:text=The ASUS GeForce RTX 4060 Ti Dual with,out whether there's any performance compromises to accept.

 

This way you only loose 4 lanes.

[Tridefender]

1 minute ago, Blue4130 said:

https://www.techpowerup.com/review/asus-geforce-rtx-4060-ti-dual-with-m-2-slot/#:~:text=The ASUS GeForce RTX 4060 Ti Dual with,out whether there's any performance compromises to accept.

 

This way you only loose 4 lanes.

They don't offer the equivalent for 4060ti 16gb variant, need that extra vram for AI purposes

Yeah that card does suck on price-value ratio but i need the extra vram, come to think of it, it's better than 5070ti, which would barely house deepseek-r1-14b. Funny that nvidia made us choose between running fast but small models, or slow but big models