What will happen? if I put a PCIe 4.0 SSD in a "PCIe 3.0 X4 to NVME Adapter" on MB's PCIe 4.0 lane?

[ElectronicGuitar]

My motherboard is X570 (MSI X570s Edge MAX)

I plan to add an additional NVME SSD on my MB, probably PCIe 4.0 X4

I have a PCIe 3.0 X4 to NVME expansion card at hand (Orico PDM2)

So I was wondering what will happen, if I put PCIe 4.0 SSD on a PCIe 3.0 Adapter, on MB's PCIe 4.0 lane? assuming they are all X4 lane

Do I get PCIe 4.0 speed? or the expansion card will force SSD to run at PCIe 3.0?

 

As far as I know, these expansion card doesn't have logic chip/PCIe Bridge chip, so it just basically wires that convert PCIE to NVME socket.

 

Reason being, I am deciding between Crucial P3 Plus and P3. The major difference between the two is PCIe4.0, and of course, price. If the adapter could potential run on PCIe 4.0 like some B450 board, I will take the P3 Plus, otherwise, there is no point expending extra.

 

 

[C2dan88]

5 minutes ago, ElectronicGuitar said:

or the expansion card will force SSD to run at PCIe 3.0?

This.

Motherboard/Chipset becomes the limiting factor if it only supports PCIe 3.0.

[johnno23]

it will work which is the most important...do it myself as I run 5 x ssd and only have 3 m.2 slots on the motherboard

I use it to simply store movies games etc and no issues with playback at all......

[RokinAmerica]

Slowest point is the fastest it can run. In real life, you will not notice any difference unless there is a specific use case.

[kokosnh]

The adapter is only changing the PCIe to M.2, there is no Logic in it , so if the PCIe 4.0 signaling is ok, it will work just fine on PCIe 4.0

 

but tell us the SSD, the mobo, and the adapter model.   

[ElectronicGuitar]

On 4/2/2023 at 10:06 PM, kokosnh said:

The adapter is only changing the PCIe to M.2, there is no Logic in it , so if the PCIe 4.0 signaling is ok, it will work just fine on PCIe 4.0

 

but tell us the SSD, the mobo, and the adapter model.   

MOBO: MSI X570s Edge MAX Wifi

Adapter: Orico PDM2

SSD: I am deciding between Crucial P3 or P3 Plus

 

[ElectronicGuitar]

On 4/2/2023 at 12:38 AM, C2dan88 said:

This.

Motherboard/Chipset becomes the limiting factor if it only supports PCIe 3.0.

The mobo and chipset do support PCIe 4.0, only the adapter is 3.0, but I just checked my adapter, there is no PCIe bridge chip or similar on the adapter, just few resistance. 

Not sure if the adapter is capable to run PCIe 4.0 signals 

 

[kokosnh]

Crucial P3 and P3 plus is the same SSD, it’s Phison E21T DRAMless + 176l QLC micron NAND. 
 

it’s just that P3 is locked to the PCIe 3.0, and that’s it.    
 

If the price is more then 5% up from the P3, i don’t see any reason to go for the P3 plus.   
 

and i wouldn’t buy that ssd, as I like faster E18 TLC ones, but that is me.   I just like fast SSD.    
 

as for the adapter, i would just try and see if there are errors, if nit, that it’s good.  
 

it’s like 5cm of copper traces, if could just be good enought for PCIe 4.0.    You have to try... 

 

 

[ewitte]

On 4/5/2023 at 7:54 AM, ElectronicGuitar said:

The mobo and chipset do support PCIe 4.0, only the adapter is 3.0, but I just checked my adapter, there is no PCIe bridge chip or similar on the adapter, just few resistance. 

Not sure if the adapter is capable to run PCIe 4.0 signals 

 

Dumb adapters shouldn't matter it just maps the pins on the m.2 drive to the pins in the PCIe slot.  If its like the 10Gbit/2xNVME QNAP card I have, that would matter because it has a PEX switch built in.