Reddit mentions of StarTech.com 2 Port USB 3.1 (10Gbps) Card - 2X USB-A - PCIe USB 3.1 Card with Type-A - PCI Express - Supports UASP

How big is your planned playspace?

Additional sensors, cables to extend the headset USB/HDMI. Avoid going above 2m extenders as you may have issues and need HDMI repeaters.

PCI Card for people with substandard USB subsystems

These are the good cards which work for most people and are recommended by Oculus

StarTek 2 port card (1 controller) – Cheaper StarTek option that could be used for 2 sensors or a sensor and headset.

https://www.amazon.com/gp/product/B013HT6K3Q

Supported Inatek 4 port card (1 controller) – Don't get the 5 or 7 port card as the design is not really suited for Rift sensors.

https://www.amazon.com/Inateck-Superspeed-Ports-PCI-Expansion/dp/B00B6ZCNGM

Use the Inatek for your two front facing cameras and nothing else. Plug your third or fourth USB 2.0 camera and Rift HMD into your motherboard.

Supported StarTek 4 port card (2 Controllers) – Optional middle tier PCI card solution which can run all four sensors or 3 sensors and HMD. Equivalent to two Inatek cards.

https://www.amazon.com/exec/obidos/ASIN/B00HJZE9VK

Supported StarTek 4 port card (4 Controllers) – Optional top of the range PCI card solution which can run all four sensors or 3 sensors and HMD. Equivalent to four Inatek cards.

https://www.amazon.com/exec/obidos/ASIN/B00HJZEA2S

HDMI and USB Cables

2m HDMI cable that works for most extending the headset

https://www.amazon.com/gp/product/B00JJ519KC/

2m USB 3.0 cable that works for most extending the headset

https://www.amazon.com/gp/product/B00CFL6ARO

More cable options here - https://www.reddit.com//r/oculus/wiki/extension_cables

Edit: You again :) I've responded to 3 of your posts today :) Seems like you made a decision. Some more stuff below you could think about.


Replacement Interfaces, Covers and Foam Inserts

VR Cover is what you need when you have sweaty friends who leave your headset foam soaking wet and gross.

I'd recommend the new facial interface with easily swappable foam pads. Swap out that soaking wet foam in seconds for the next person using the Rift.

• Replacement Interface – https://vrcover.com/product/oculus-rift-facial-interface-foam-replacement-standard-set-2/
  
• Nicer Foam Cover for above – https://vrcover.com/product/oculus-rift-foam-replacement-velour/
  
  Alternatively you can go the cheap option of just a cover for the existing rift interface but it takes a bit longer (~30 seconds) to swap and is nowhere near as comfortable.
  
  
• Cover for stock Rift foam – https://vrcover.com/product/oculus-rift-vr-cover-nosefree/
  
  While the cheap option is great the newer facial interface and velour foam pads are much more comfortable and better than the stock foam.
  
  All of the above are washable as well.
  
  For glasses wearers that do offer the replacement interface in a "deeper" version but it may impact on the FOV (Field of View) of the Rift as your eyes are further from the lenses. I have never tried these.
  
  Video explaining how they work and why they are different
  
  https://www.youtube.com/watch?v=rGeoPKTqKNo
  
  Screen Protectors
  
  These Healingshield 48mm curved watch face protectors work a treat if you want to protect the lenses from scratches. I was skeptical they might impact the visuals but I honestly can't notice them at all. Don't buy any cheap versions of these as they are usually flat and don't sit on the curved lenses of the Rift properly. These ones fit perfectly and have no issues with bubbling.
  
  
• https://www.ebay.com.au/itm/Watch-Face-Clear-Protector-Screen-Protector-Surface-Guard-Film-Healingshield-3x/122015221004?hash=item1c68ac850c:m:mrjCq8F8QOqCjIrvAdvmJ9g
  
• https://www.amazon.com/Healingshield-Watch-Protector-Guard-1-89in/dp/B00SJ22CY8
  
  Mounting Sensors
  
  If you want to mount the sensors in the corner of your room you can unscrew the sensors from their base and attach them to wall mounts.
  
  If you have access to a 3D printer these. I use them for three of mine
  
  
• https://www.thingiverse.com/thing:1772848
  
  or these
  
  
• https://www.buymobius.com/products/vhb-adhesive-camera-mount
  
• https://www.amazon.com/Adhesive-thread-Mobius-Actioncam-Novotm/dp/B00GEGA98M

Excuse me, I wasn't actually meaning a USB hub. Instead I was referring to this USB 3.1 card. I mean, it really sounds like there is virtually no real benefit from going the extra mile and getting 3.1 slots, but if it gives me just that little bit of performance edge then I'd be willing to pay. I'm running an SLI setup with two massive cards so I'm not really sure I could even manage to squeeze a hub in there anywhere. So this may not be a viable solution, but I guess I can try like hell. :)

I've been looking at motherboards and cases and I'm really confused on matching up USB ports.

So obviously, rear panel usb ports will be found on the back of your case, and those depend entirely on your motherboard.

But what about front USB ports, the ones that case makers already include? Correct me if I'm wrong, but, that all depends on the internal io connectors/headers of the motherboard, where a single header should support 2 ports of it's type?

And where does adding USB ports belong in this? Whether through a pci slot in the back or a 5.25" bay in the front?