Question Can I do Both GPU and M.2 SSD with PCI-E 5.0?

braxus

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I have a current new motherboard which supports PCI-E 5.0 on both the GPU slot and also the M.2 slots. Yet my motherboard (Gigabyte X870E Aorus Pro) says you cant do 2 things in 5.0 from what I gather. Something about shared lanes. If I got a RTX 5080 and also the upcoming Samsung 9100 Pro 8TB M.2 SSD, of which both devices support PCI-E 5.0, what do you suggest in terms of how to install these in which slots? Will I have to downclock the SSD just so the GPU can run full out in speed? Or am I missing something in regards to my board which would allow both devices at full speed?
 
what do you suggest in terms of how to install these in which slots?
In real world scenario's you won't be able to tell the difference. On that note, what sort of tasks will you be taxing the system with?

Will I have to downclock the SSD just so the GPU can run full out in speed?
Lane sharing doesn't work like that, it's beyond control via software. It's how the lanes are wired by AMD and the board makers.

Or am I missing something in regards to my board which would allow both devices at full speed?
Are you looking at a single PCIe5.0 drive and a PCIe5.0 discrete GPU?

Please include the specs to your build like so:
When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.

If you state it's mentioned in your sig space, please understand that sig space specs can and will change over time, rendering this thread moot to the end user in the same boat as you're in now. Hence why we ask users to include them in the thread's body.
 
According to my reading of the specs, M2A_CPU with a Ryzen 9000 processor will always support PCIe 5.0 x4.

The x16 GPU slot shares lanes with M2B_CPU and M2C_CPU. If one or both of those other M2 slots is populated, the GPU will operate at x8, with the other 8 lanes split between the two M.2 slots, but they will still be running at PCIe 5.0.

The chipset also supports M2D_SB at PCIe 4.0.

Nothing indicates that anything will operate at a lower PCIe speed, but your GPU will be operating with half the lanes available if you use the 2nd or 3rd M.2 slots. (Performance would be equal to PCIe 4.0 x16.) Even if you did do that, you may lose like 1 to 2% of your GPU performance (I've only seen one site that tests at different PCIe speeds and can't remember which one), but it doesn't seem like it will be an issue in your case, and you can always use the 4th M.2 slot if you want secondary storage and don't want to affect the GPU.