Out of PCIe lanes, internal capture card via Thunderbolt?

[BeastChan23]

Hey folks, I've had my system for a while now, but finally decided to grab a gen 4 SSD and install it in addition to my current gen 3 drive.
And of course, that second m.2 slot disables the x4 PCIe slot I used for my capture card.

So my options are as follows:
a. Use capture card on a CPU PCIe slot which would cut my graphics card slot to x8 speed. (Free)
b, Buy USB based capture card instead, and sell internal card. ($150~ - cost of selling internal card)

c. Get external GPU enclosure and use for internal capture card. ($200+)
d, Get x570 board for more PCIe lanes ($200+)

And something that just hit me while typing this up:
e. External m.2 enclosure for secondary SSD ($20+, $100 for fancy dock with usb ports that would be nice)
f. Install second m.2 drive in Server, and share the drive to LAN via 2.5GbE? (free)

This secondary drive would only be used for random files and games that I want to install but not on gen 4 drive, or a SATA SSD I already have.
The external m.2 enclosure/dock seems like the most cost effective outside of the free option.
Either way, has anyone had any experience using a PCIe card on an external GPU enclosure or similar style units?

System Specs:
5900x
32GBs of ram
Gigabyte B550 Vision D-P
RTX 3080
Elgato 4K60 PRO
2x M.2 drives, 1x SATA SSD

Yes this board supports TB3 as well as USB 3.2 gen 2

Edit, looks like they have a video on this specific use case where one would slap the internal card into an enclosure. So while not officially support, it will work.

 

[thewelshbrummie]

Why is the GPU in the x4 slot? It should always be in the slot closest to the CPU (the top x16 slot) for best performance - a 3080 will undoubtedly suffer if run with only 4 lanes, regardless of PCI-E version.

 

To be frank, we are talking Verge PC levels of a poor build if you've put the GPU in the x4 slot! You're not out of lanes - but have apparently ignored using the top PCI-E slot for reasons that only you can answer.

 

Looking at the manual you are correct in that the x4 slot is disabled when using the 2nd m.2 slot. But you still have 2 slots left so use them.

• Put the GPU in the top x16 slot.
• Put the capture card in the x8 slot.

So as you've outlined in option a, but with the cards swapped around - you should put the GPU in the PCI-E slot that takes it's lanes directly from the CPU. The point is that by bypassing the chipset when using that slot, you reduce latency and therefore may get more performance.

 

Even if you only get 8 lanes to the GPU it shouldn't cause any problems for the 3080. B550 supports 20 lanes at PCI-E v4 - 4 lanes for the m.2 you've just installed, and 16 for the top slot. Even if that's split PCI-E 4.0 x8 (.e. 8 lanes) will be fine for a 3080.

[BeastChan23]

Seems like you've misread somewhere, my graphics card is indeed in the top slot (x16), the capture card can be put in the x8 slot and that would cut the GPU slot to x8 also.

The configuration you've mentioned is exactly how I have it setup now.

While everything is working fine now I'm considering an eGPU enclosure as I've found one locally for $100, but right it shouldn't really affect performance of my GPU for now.

[Shzzit]

4 hours ago, BeastChan23 said:

Seems like you've misread somewhere, my graphics card is indeed in the top slot (x16), the capture card can be put in the x8 slot and that would cut the GPU slot to x8 also.

The configuration you've mentioned is exactly how I have it setup now.

While everything is working fine now I'm considering an eGPU enclosure as I've found one locally for $100, but right it shouldn't really affect performance of my GPU for now.

Looks like you said “And of course, that second m.2 slot disables the x4 PCIe slot I used for my graphics card.”  So not sure. 

[BeastChan23]

Ooop typo, fair enough.

Sorry about that, edited.