Question WD SN850 NVMe SSD --- only around 1700 read/write on PCIe 3.0 ?

darkbasicmaster

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In crystal disk I'm getting horrible speeds even on pcie 3.0. I see some of these guys getting 3500 on 3.0 and idk how, maybe I have a bad drive? It's connected on the first slot, and I also noticed if I verify the integrity of some game files on steam, it's literally worse than an HDD ?

MSI Z490 Carbon Gaming Wifi

3080 Ti

10900k

32 GB RAM

 

darkbasicmaster

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Motherboard is a MSI Z490 Carbon Gaming Wifi. I have it hooked up into the first slot, M2_1, and only my OS in the first sata port. I cannot reach the 3.5 GB/s that gen3 is capable of, and MSI support wants to blame it on my 10900k since the first slot is connected to the CPU.

I cannot find anywhere in the bios of this m2 slot being limited to 2 lanes instead of 4. My WD dashboard says it's connected to Gen3 on 4 lanes so something is halfing my speed here.

Here is my full setup

i9-10900k 4.8 GHz
4x 8GB DDR4 3.8 GHz
3080 Ti in PCI_E1 slot
Soundblaster soundcard hooked up in x1 mode in PCI_E5 x16 slot
SSD in sata 1
SN850 in M2_1 slot

Please help me

Picture attached.
 
I see you have an additional card plugged in, a Soundblaster? This will require a PCI-e lane, and, the most logical place to steal it from might be your storage.

Perhaps experiment with removing the Soundblaster and retesting...(as a minimum, might be some bandwidth sharing limiting your speeds)

Does your mainboard have a pair of NVME slots?
 

itrip

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I see you have an additional card plugged in, a Soundblaster? This will require a PCI-e lane, and, the most logical place to steal it from might be your storage.

Perhaps experiment with removing the Soundblaster and retesting...(as a minimum, might be some bandwidth sharing limiting your speeds)

Does your mainboard have a pair of NVME slots?
What mdd1963 is saying seems to me the most logical at this point in the diagnosis, I would have thought differently if you where talking about your copy speed witch is entirely dependent upon what kind of data you copy and how fast it can then go, but it's hard to argue that there is something not quite right if you see a problem in a synthetic bench.
 
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darkbasicmaster

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I see you have an additional card plugged in, a Soundblaster? This will require a PCI-e lane, and, the most logical place to steal it from might be your storage.

Perhaps experiment with removing the Soundblaster and retesting...(as a minimum, might be some bandwidth sharing limiting your speeds)

Does your mainboard have a pair of NVME slots?
Yeah so I thought that might be the problem, but I removed the card and tested the speeds again. The exact same thing, I have no idea what is going on here, this bios isn't very helpful either, couldn't find anything there.
And yeah it does have a second slot, and that's connected to the chipset, haven't tried it yet but why in the world would the first slot be limited to 2 lanes only or be getting x2 speeds when it's supposed to be Gen 3 x 4, even the wd dashboard confirms that? And it's not my 10900k, msi support tried to blame it on that but they don't know what they're talking about.

I know on some other z490 motherboards like asus, there is a lane allocation option, and you can change it from x2 to x4, but I have no such option
 

itrip

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You could try updating BIOS to latest version.
It's funny that this is always what usually helps, the question in my mind now is why doesn't it work as advertised without doing said bios update, if that doesn't work either, maybe you should look into getting to returning & replacing the parts once identified witch are misbehaving.

Maybe it's because you have 400GB's on this drive already, and that's affecting the speed, probably not, but just a thought.
 
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darkbasicmaster

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It's funny that this is always what usually helps, the question in my mind now is why doesn't it work as advertised without doing said bios update, if that doesn't work either, maybe you should look into getting to returning & replacing the parts once identified witch are misbehaving.
Did a bios update nothing. I am curious though, my manual block diagram says there is a switch between some of the sata ports and the m.2 slots, can this have anything to do with it? I think this is an auto switch that just disables the sata ports, but idk what else it could be at this point

 

darkbasicmaster

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I recall an big issue on this, I think i researched into the SN850, people were having problems last year and they were talking about disabling your wifi and ethernet to get from 128 to 256 lanes or something
 

darkbasicmaster

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Yeah it states it supports PCIe 3.0 x 4 lanes, I know this is a gen4 SSD, but even on Gen3 I see people getting half of the rated speed which is about 3.5 GB/s, I'm getting half of the Gen3 4 lane speeds.

I looked over my manual up and down, can't find anything helpful
 

itrip

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Yeah it states it supports PCIe 3.0 x 4 lanes, I know this is a gen4 SSD, but even on Gen3 I see people getting half of the rated speed which is about 3.5 GB/s, I'm getting half of the Gen3 4 lane speeds.

I looked over my manual up and down, can't find anything helpful
I hear you, I don't have anything more to add, I would RMA the drive and the motherboard, and once you get new part see if the problem persists, but you might want to wait on that if you can maybe somebody with more ideas about what you can try will come allong and read your post and try to help out.
 

darkbasicmaster

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I hear you, I don't have anything more to add, I would RMA the drive and the motherboard, and once you get new part see if the problem persists, but you might want to wait on that if you can maybe somebody with more ideas about what you can try will come allong and read your post and try to help out.
Yeah I know that's what everyone wants to suggest, but it wouldn't be exactly half the speed of what Gen 3 is capable of if it was a bad drive. Something else is going on here, trying to talk with MSI support but that's always a joke
 

itrip

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Yeah I know that's what everyone wants to suggest, but it wouldn't be exactly half the speed of what Gen 3 is capable of if it was a bad drive. Something else is going on here, trying to talk with MSI support but that's always a joke
And I can't find hardly anyone with the same issue i have relating to this exact motherboard, so I think I'll have to rma the drive, then go from there

Maybe that's the only way to solve the problem, but it might also not be.
I feel bad with you because something like this should not happen if you buy quality hardware.
As a last resort have you tried benching the drive without much data on it, like I said above could be your problem, but thats highly unlikely, but if you try it atleast you will rule that out too.
 

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