Question / Help Graphics card performance [x16 vs x8]

[SAngeli]

Hi,
I am building a new PC primarily for OBS Studio using two 1080p/50 cameras and two Blackmagic Design capture cards: "Intensity Pro 4K" and "DeckLink Mini recorder 4K". I might also use an IP camera via LAN.

I have an Asus X99-A II mobo with 16GB RAM, an Intel I7-6800K (Socket LGA2011-V3) CPU - 28 lanes - and a GigaByte GV-N105TG1 GAMING-4G GPU. Moreover, I will be using an M.2 PCIe nVME SSD - OCZ RVD400.

The doubt I have is "CPU lanes" something I was not so knowledge about till now (and still am learning). I was hoping to have a PCIe configuration of x16/x4/x4 (GPU/Intensity Pro/DeckLink) but with the M.2 SSD I believe I max out the CPU lanes because I was told (do not know if this is correct) that I have to also consider Chipset and other onboard components (like NIC, SATA disks, USB ports....) lane usage. Going with a Xeon CPU is not the case: main point will be up to 40 lanes benefit but it will cost me way more money even if my mobo supports Intel Xeon E5 v3 LGA2011-3 CPU series.

So I might end up having a PCIe configuration of x8/x4/x4 This way I will end up with some free lanes (which is a good thing in a sense). I have to see which is best PCIe cards placement on PCIEX16_ slots on the mobo.

Is it a big deal for OBS Studio and the "final live streaming result" having my GPU running at x8 rather than x16 considering the overall hardware I am using?
I asked around and briefly read some benchmarks: I noticed that the difference varies from software to software but is not that big difference: just a minor difference.

Any suggestion/comment please so that I can be assured that hardware I already have is ok for this project?
Many thanks...

 

[SAngeli]

Here is a link to an interesting YouTube video comparing Gen. 3.0 PCIe x16 version x8.
I believe the answer to this thread question would be "not to worry at all, go safely with x8/x4/x4 config". Thou, I wish and must hear from you guys who are "the expert" for OBS.
Thanks...

 

[Harold]

I believe the answer to this thread question would be "not to worry at all, go safely with x8/x4/x4 config

If you're ONLY gaming or ONLY streaming on the system, this would be the case.
But if you're doing both, you generally NEED the gpu running at x16.

 

[SAngeli]

Hi Harold,
thank you for your reply.

If you're ONLY gaming or ONLY streaming on the system,

To be precise, I will be doing always one thing at the time, meaning:
- live streaming video content, at 1080p/50, of what my 2 Blackmagic Design capture cards will acquire from my 2 handycams
OR
- editing video with a video editing software
OR
doing regular office stuff (browse the Internet, write emails, Word....).

But I will not use this workstation for gaming: it is not the type of project I have to work on.

Will I be fine with GPU running at x8?

From what I was told OSB uses GPU for Compositing and CPU for Rendering final project which will be then streamed to the Internet. So, CPU would/should be far more important than GPU, if I am not wrong saying this. At least his is what I learned.
Also, another consideration if valid: if those two capture cards will use up to 8 lanes (x4+x4) wouldn't this require a total GPU 8 lanes, or this is not how it works?

Thank you

 

[Harold]

The way that x99 based boards work, if you have enough pci-e lanes on the cpu to maintain everything, the GPU will run at x16.

Only if the combined usage across ALL cards is greater than the pci-e lanes available on the cpu will the GPU end up in x8 or lower assuming you install the gpu in PCIE16-1 on the board.

Your planned setup will be using 28 lanes based on the parts you listed, and depending on how things are hooked up with the board, you may actually have some lanes on the cpu left over.

Generally x8 is fine for ANY non-gaming streaming since you're not trying to also squeeze a game in.

 

[SAngeli]

Hi Harold,
thanks for your reply.

Generally x8 is fine for ANY non-gaming streaming since you're not trying to also squeeze a game in.

Excellent!!!

Many thanks....