3080 x8 need advice

[cruisinbeatz]

Hey folks, ok just a quick one here as I cant seem to follow the manual or I'm just thick, either way...

I have:
3900x
x570 Asus Hero WiFi
64GB Ram
2x NVME 1TB (1TB in each of the 2 slots)

Now here's my issue, with that setup I was running my 1060 6gb (x16 slot 1)perfectly fine at x16 with my 2nd x16 slot running a asus hyper m.2 card (x16 slot 2) with 2x 1tb drives. which I think also ran at x16 but had to enable raid on the 2nd slot to split it to 2x x8 slots? I think? Anyhooo...

Thanks to OCUK I eventually got my 3080 delivered (thanks again guys, I know you were under pressure) so I changed things up a little. Similar setup as before however instead of using the asus hyper car as its a big bit of kit (I thought it would block airflow to the new gpu which there was less than an inch clearance) I would get a PCIe x16 nvme holder/adaptor or whatever you want to call it, the sabrant one as its small and nifty. I plugged it into the 3rd x16 slot and moved my other expansion card up to my 2nd slot. (usb 3 gen 2 card, this previously was in the 3rd slow I forgot to mention)

So in changing things about my gpu slot has now went to x8 instead of x16, can someone advise me on where I've went wrong here as its racking my very tiny brain.

I hope I explained it correctly. Thank you in advance.

 

[Captain_Bosh]

In short sounds like using the third x16 PCI-E is limiting your bandwith to x8 speed. Remove the NVME adapter to get it back up to x16 for your GPU.

Why don't you use the 2 NVME slots on your motherboard instead of adapters?

 

[cruisinbeatz]

In short sounds like using the third x16 PCI-E is limiting your bandwith to x8 speed. Remove the NVME adapter to get it back up to x16 for your GPU.

Why don't you use the 2 NVME slots on your motherboard instead of adapters?

Thanks for your reply, on way home from work her so I will try that first... I am using them however I have more nvme drives than ports on the motherboard hence using the adaptor unfortunately.

 

[Orcvader]

Looking at the manual the second and third PCIe x16 slots are linked with the first slot, so no matter where you plug the adapter in, it will force the first slot to go into x8 mode. Assuming you kept the same board, that means the 1060 should have been running in x8 mode as the Asus NVME adapter was using the second x16 slot. Are you absolutely sure it was running in x16 mode?

How many NVME drives do you have?

 

[cruisinbeatz]

Looking at the manual the second and third PCIe x16 slots are linked with the first slot, so no matter where you plug the adapter in, it will force the first slot to go into x8 mode. Assuming you kept the same board, that means the 1060 should have been running in x8 mode as the Asus NVME adapter was using the second x16 slot. Are you absolutely sure it was running in x16 mode?

How many NVME drives do you have?

Yes 100% it was x16 and then has the Asus hyper card with 2 drive in it and it was running 8x and then the USB 3 card was in the 3rd slot. Wouldn't have anything to do with Gen 3 or 4 perhaps? I know it's not the end of the world to run at x8 but will be hateful if I have to take all out to get x16 again. Wonder do I have to tell the motherboard it's gen 4 gpu? The bios was updated last month too.

1 1tb nvme boot
1 1tb nvme in 2nd slot
1 2tb nvme in pcie adaptor

I have 2x 1tb nvme drive but have external caddys for those.

 

[Penfold101]

If I understand it all correctly, you can’t have one slot running at 16x if you have anything else using the PCI slots. You have 24 lanes to the CPU, and the NVME slot on the MB will use 4 of them, and the chipset will use another 4. Using a GPU in the top one and nothing else will give it the full 16x, but using any other PCI slot for a thing else will split them to 8x each - there’s no way around it. The chipset lanes can be slept down more I believe, through the various sata ports etc, but as far as I know the PCI lanes are limited in what you can do with them.
I think this is correct - anyone else who knows more feel free to call me an idiot…

 

[cruisinbeatz]

If I understand it all correctly, you can’t have one slot running at 16x if you have anything else using the PCI slots. You have 24 lanes to the CPU, and the NVME slot on the MB will use 4 of them, and the chipset will use another 4. Using a GPU in the top one and nothing else will give it the full 16x, but using any other PCI slot for a thing else will split them to 8x each - there’s no way around it. The chipset lanes can be slept down more I believe, through the various sata ports etc, but as far as I know the PCI lanes are limited in what you can do with them.
I think this is correct - anyone else who knows more feel free to call me an idiot…

You know what I think your right, I could swear the 1060 was at x16, I would have bet my life on it I was that certain but when you have explained it there it makes sense. I removed both the nvme and usb car and hey ho up to x16.... ahhh...... Will I really be losing out on that much performance running x8 for a few months to I get something else sorted or arranged?

 

[Penfold101]

You know what I think your right, I could swear the 1060 was at x16, I would have bet my life on it I was that certain but when you have explained it there it makes sense. I removed both the nvme and usb car and hey ho up to x16.... ahhh...... Will I really be losing out on that much performance running x8 for a few months to I get something else sorted or arranged?

Gamers Nexus tested this I think, and essentially no - even the 30 series can’t max out the Gen 3 PCI link at 8x so it’s not an issue (haven’t been to YouTube to double check that, might be worth a look)

Also of interest is the HyperX card - if you wanted all 4 slots on that used you couldn’t have a GPU, as each drive physically uses 4 lanes. You’d need a Threadripper platform which has 128 lanes to play with, and that’s on a different budget all together…

 

[Orcvader]

If I understand it all correctly, you can’t have one slot running at 16x if you have anything else using the PCI slots. You have 24 lanes to the CPU, and the NVME slot on the MB will use 4 of them, and the chipset will use another 4. Using a GPU in the top one and nothing else will give it the full 16x, but using any other PCI slot for a thing else will split them to 8x each - there’s no way around it. The chipset lanes can be slept down more I believe, through the various sata ports etc, but as far as I know the PCI lanes are limited in what you can do with them.
I think this is correct - anyone else who knows more feel free to call me an idiot…

Correct. The only PCIe slot controlled by the chipset for this particular motherboard is the x1 slot, which sadly won't work for OP's adapters. I suppose he can move his USB 3.1 gen 2 card but all that will do is allow the second slot to run in x8 instead of x4.

You know what I think your right, I could swear the 1060 was at x16, I would have bet my life on it I was that certain but when you have explained it there it makes sense. I removed both the nvme and usb car and hey ho up to x16.... ahhh...... Will I really be losing out on that much performance running x8 for a few months to I get something else sorted or arranged?

In terms of gaming you won't notice any difference dropping from x16 to x8, especially with PCIe gen 4.

 

[Maldoror]

Odd. The Gen3/4 thing on the GPU should not really matter at all here. According to the manual, the pcie allocation for both 2nd and 3rd gen Ryzen is:

PCIE 1 16x
PCIE 2 empty
PCIE 3 empty

and

PCIE 1 8x
PCIE 2 8x
PCIE 3 empty

and

PCIE 1 8x
PCIE 2 8x
PCIE 3 4x

with the only difference on newer Ryzens being with those running 4.0 instead of 3.0 mode (page 1-8 of your manual).

The likes of GPU-Z can sometimes make errors - especially when cards are in idle/standby modes. I'd wonder if the 1060 was really running 16x with things running in pcie 2 or 3 as well.

Either way though, I don't think you'll lose much performance from running 8x 3.0 on the 3080. Not worth losing storage space for what - for my money - will be barely benchable and less than a percent.

 

[cruisinbeatz]

Gamers Nexus tested this I think, and essentially no - even the 30 series can’t max out the Gen 3 PCI link at 8x so it’s not an issue (haven’t been to YouTube to double check that, might be worth a look)

Also of interest is the HyperX card - if you wanted all 4 slots on that used you couldn’t have a GPU, as each drive physically uses 4 lanes. You’d need a Threadripper platform which has 128 lanes to play with, and that’s on a different budget all together…

Ill do more research to see whats going on lol.

I bought it as it was the cheapest way I could add more nvme drives at the time and only had 2x 1tb nvme drives in it. Great card and did have 4 drives in it once but yea I remember there was an issue with it but cant remember what it was. perhaps that was the issue.... No definitely not going down the route of Threadripper, Ill make do with what I have here or use usb externals or something. Would love some way of mounting them all inside some form of multi external enclosure but from what I see they are all mega bucks. They will do as extra storage for ps or xbox or something lol

 

[cruisinbeatz]

Correct. The only PCIe slot controlled by the chipset for this particular motherboard is the x1 slot, which sadly won't work for OP's adapters. I suppose he can move his USB 3.1 gen 2 card but all that will do is allow the second slot to run in x8 instead of x4.



In terms of gaming you won't notice any difference dropping from x16 to x8, especially with PCIe gen 4.

Thanks for the info, yes thats what I was hoping for anyhow. Fingers crossed.

Odd. The Gen3/4 thing on the GPU should not really matter at all here. According to the manual, the pcie allocation for both 2nd and 3rd gen Ryzen is:

PCIE 1 16x
PCIE 2 empty
PCIE 3 empty

and

PCIE 1 8x
PCIE 2 8x
PCIE 3 empty

and

PCIE 1 8x
PCIE 2 8x
PCIE 3 4x

with the only difference on newer Ryzens being with those running 4.0 instead of 3.0 mode (page 1-8 of your manual).

The likes of GPU-Z can sometimes make errors - especially when cards are in idle/standby modes. I'd wonder if the 1060 was really running 16x with things running in pcie 2 or 3 as well.

Either way though, I don't think you'll lose much performance from running 8x 3.0 on the 3080. Not worth losing storage space for what - for my money - will be barely benchable and less than a percent.

Funny enough it was GPU-Z I was using, perhaps that was the issue alright, I know this time I viewed it in the bios as x8 and I suppose I could sit and modify the pc again and start putting the 1060 in but as it sits, its too much effort for what its worth. You guys have explained it better than what I can read off my manual so thank you to all who helped this small brained guy out. VERY much appreciated.

 

[Penfold101]

Ill do more research to see whats going on lol.

I bought it as it was the cheapest way I could add more nvme drives at the time and only had 2x 1tb nvme drives in it. Great card and did have 4 drives in it once but yea I remember there was an issue with it but cant remember what it was. perhaps that was the issue.... No definitely not going down the route of Threadripper, Ill make do with what I have here or use usb externals or something. Would love some way of mounting them all inside some form of multi external enclosure but from what I see they are all mega bucks. They will do as extra storage for ps or xbox or something lol

I learnt all of this with the plan of having all my storage on NVME and being pointlessly fast, and wondered why there was a lack of converters for NVME to Sata and never more than one slot on a PCI adapter. Turns out the architecture and protocol is different from sata so you can’t convert between them, and it needs the PCI lanes to work. Now I’m just going to get sata SSD’s with a Sedna PCI adapter - don’t need the NVME speeds for my general storage anyway…

 

[Deleted member 66701]

If you are using that many NVME devices you need to look at a HEDT platform like Threadripper.