PCIE Calculation help

[StevenDaSun]

So I'm planning to buy a 3900X along with UNRAID but I'm not sure if I'll have enough PCI Lanes. (If so please give me recommendations for another CPU if so)
GTX 1080 for one Gaming VM

RTX 2060/70 for the other VM
NVIDIA P2000 (or higher) for Plex Transcoding

5 x 8TB SATA Storage (maybe 4 drives instead idk yet)
1TB NVME M.2
2 USB Controllers or if the Motherboard has enough USB IOMMU Groups
I think that's about it

The 3900x has 24 lanes, 4 for the chipset though, so 20 usable (This is Gen 4 PCI btw, so i might be able to get away with things in 8x instead, and idk how much the P2000 needs for Plex Transcoding)
I can make compromises too

Edited May 16, 2020 by StevenDaSun

[Curious Pineapple]

I wopuld suggest Proxmox instead of UNRaid, mainly as it's free.

[StevenDaSun]

1 minute ago, Curious Pineapple said:

I wopuld suggest Proxmox instead of UNRaid, mainly as it's free.

Oh I'm already really comfortable with unraid, especially with using dockers and user scripts. (and I already paid for it for the server I'm currently using and planning to replace)

[Electronics Wizardy]

1 minute ago, Curious Pineapple said:

I wopuld suggest Proxmox instead of UNRaid, mainly as it's free.

and it does storge better wswell, but. bit harder to use.

 

4 minutes ago, StevenDaSun said:

The 3900x has 24 lanes, 4 for the chipset though, so 20 usable (

Don't look at lanes from the cpu, look at how your board lets you use them, but this should be dooable on x570. So put the p2000 on the top slot(probalby not needed though, unless you have very heavy plex use), put the other gpus in other slots, so the last gpu runs off the chipset. 

[StevenDaSun]

2 minutes ago, Electronics Wizardy said:

Don't look at lanes from the cpu, look at how your board lets you use them, but this should be dooable on x570. So put the p2000 on the top slot(probalby not needed though, unless you have very heavy plex use), put the other gpus in other slots, so the last gpu runs off the chipset. 

Ah really? Okay I'll give it a shot in about a week or two. But can you explain why the lanes shouldn't be much of an issue? And later when I find a board can I show it to you before I buy, to figure out how the motherboard would utilize the lanes?

[Electronics Wizardy]

2 minutes ago, StevenDaSun said:

Ah really? Okay I'll give it a shot in about a week or two. But can you explain why the lanes shouldn't be much of an issue? And later when I find a board can I show it to you before I buy, to figure out how the motherboard would utilize the lanes?

the cpu lanes and chipset lanes don't matter as motherboards often won't use them all of have other limits, so even if your cpu has 20 lanes and the chipset has like 16, doesn't mean you can use them all.

 

Look at the board specs, it tells you what slots can run at what speeds, and if there running of the chipset or cpu.

[StevenDaSun]

Ohhh thats wild, I didn't know the chipset offered lanes too, so I would theoretically have 36 usable lanes.

Okay I'll do some more research on a motherboard that available and one I like. Thank you so much, that makes soooo much more sense

[Electronics Wizardy]

6 minutes ago, StevenDaSun said:

Ohhh thats wild, I didn't know the chipset offered lanes too, so I would theoretically have 36 usable lanes.

Yea, but this depends on the chipset. Also these lanes are either sata or pcie, so its up to the mobo maaker to determine how the lanes should be used. These lanes are also used for thing like ethernet on board and other onboard devices.

[StevenDaSun]

1 hour ago, Electronics Wizardy said:

Yea, but this depends on the chipset. Also these lanes are either sata or pcie, so its up to the mobo maaker to determine how the lanes should be used. These lanes are also used for thing like ethernet on board and other onboard devices.

Ahh okay got it thanks, I'll update the forum if I find a good motherboard I think is correct.

[nick name]

Do you mind if that P2000 is running in X4 while the other cards are X8?

[StevenDaSun]

1 minute ago, nick name said:

Do you mind if that P2000 is running in X4 while the other cards are X8?

I mean if the P2000 can still be fully utilized for Plex Transcoding then sure.

[nick name]

1 minute ago, StevenDaSun said:

I mean if the P2000 can still be fully utilized for Plex Transcoding then sure.

Hmmm, I can't answer that question.  

[nick name]

3 minutes ago, StevenDaSun said:

I mean if the P2000 can still be fully utilized for Plex Transcoding then sure.

From someone on Reddit:

Quote

For 1080p h264 I saw no difference on a P2000 between PCIe 3.0 x8 and x4. I didn't test 2.0 x8 but that's the same bandwidth as 3.0 x4.

 

[StevenDaSun]

Ah I see that's pretty cool, hopefully its the same for 4K and H265 transcodes, but thanks

[StevenDaSun]

16 hours ago, Electronics Wizardy said:

Yea, but this depends on the chipset. Also these lanes are either sata or pcie, so its up to the mobo maaker to determine how the lanes should be used. These lanes are also used for thing like ethernet on board and other onboard devices.

What do you think of these (im leaning for ASUS cuz aura sync lol and i like the bios, but doesnt really matter)
https://www.microcenter.com/product/608549/asus-x570-rog-crosshair-viii-hero-(wi-fi)-amd-am4-atx-motherboard
https://www.microcenter.com/product/608667/X570_Aorus_Master_WiFi_AMD_AM4_ATX_Motherboard

Or is this too expensive and I should wait for other boards to come back in stock

[LauRoman]

Try and get a motherboard from a line that has historically had more bios updates over a longer period of time, so don't go for stuff that is too niche. (i am not sure if that asus you linked fits the criteria or not) Figure out which one is easier to downgrade bios on, if you so choose. Because with future vulnerability mitigations you might or might not want to sacrifice some performance. Considering the amount of high performance parts connected to a single cpu, and the fact that they might all run 24/7 leave some room for bios fiddling.

[StevenDaSun]

Oh I think ASUS has a decent record for keeping things up to date, like the previous ROG CROSSHAIR VI/VII HERO, they both updated right before New Years. But I see your point, that was something I never considered. So there's a good chance they'll update it for 2-3 years more since it's the only board that can support next gen Ryzen.

[nick name]

The Crosshair VIII was what I was looking at that runs those GPUs at X8 X8 X4 with a X1 slot mixed in.  

[StevenDaSun]

yeah you're right dang unfortunate (its actually 8x 4x 4x with all 3 cards in use), and the aorus is same
But would that be fine, because PCI 4th Gen has about double the bandwidth, so my GPU should be fine, no?

[Electronics Wizardy]

1 hour ago, StevenDaSun said:

yeah you're right dang unfortunate (its actually 8x 4x 4x with all 3 cards in use), and the aorus is same
But would that be fine, because PCI 4th Gen has about double the bandwidth, so my GPU should be fine, no?

well most of those cards you listed don't support 4th gen, so that won't matter.

 

That is a big limit of am4, with lanes.

 

x4 should be fine, and its not like your getting the peak performance from this system anyways.

 

Also what case? You need one that has anouther slot at the bottom.

 

Also check how these boards handle iommu groups as thas can be fun at times.

[StevenDaSun]

29 minutes ago, Electronics Wizardy said:

well most of those cards you listed don't support 4th gen, so that won't matter.

 

That is a big limit of am4, with lanes.

 

x4 should be fine, and its not like your getting the peak performance from this system anyways.

 

Also what case? You need one that has anouther slot at the bottom.

 

Also check how these boards handle iommu groups as thas can be fun at times.

Yeah i thought so thanks for verifying

Currently I have my tower in a NZXT S340 (standard white, not elite)
Probably gonna need to change it, any recommendations? (I do love white cases tho, but it doesnt really matter lol, nothing too expensive too haha, oh and with USB 3.1 Gen 2 ports)

and I'll check on the the iommu groups thanks