Latency spikes using front panel USB (3.2 Gen 1). Switched to mobo (3.2 Gen 2). Much Better. Why?

[u/Apprehensive_Mood896]

I recently saw a lot of discussion about what speed usb port should be used. Most people recommend using usb 3.2 gen 1 or higher. So I thought I was good using my front panel USB(which is USB 3.2 gen 1). I was noticing a lot of latency spikes sporadically. I switched to a usb 3.2 gen 2 on my motherboard and the latency spikes disappeared.
Is this a result of the faster USB port? or because it’s connected directly to the motherboard?
Or both potentially…?

[u/CpTKugelHagel]

Could be the newer gen, could be interference going through the cable which plugs your front panel into the mobo.

could be that the mobo is prioritizing the ports on the back over front panel, could also be that the line of sight is better from the back, depending on where your pc is located.

Could also be the Machine spirit being spiteful lmao

[u/darkwire01]

If you're on AMD, usually it's because you've selected a USB port that is directly connected to the AMD CPU usb, and IIRC if you're on Intel, it doesn't matter because they access it through an optimized pathway via PCH to the chipset that provides the USB ports.

Also on AMD, the mobos are usually supported by an auxillary USB controller to add more ports than the CPU itself can support and the auxillary USB controller is slower than the on CPU USB controller.

[u/trankillity → u/darkwire01]

I remember finding this nugget out after having my mouse have stutter lag! I believe they eventually fixed it in a BIOS update, so probably worth checking if there is any updates.

[u/crozone → u/darkwire01]

Isn't it actually the in-CPU USB controller that has all of the latency issues? Many AMD motherboards have a "VR USB" port on the back which is wired to a dedicated, external USB controller wbich has a known working configuration with drivers. This was a huge issue back of the Valve Index and would cause the cameras to stop working.

[u/Wyrade]

Front panel USB is often a separate USB hub that is connected to your main USB hub on your motherboard.
You might be able to check with usbtreeview:
https://www.uwe-sieber.de/usbtreeview_e.html

With that said, that might be irrelevant and the source of the issue could be something else.

[u/Slaughter_pit]

Should I use the front or back USB? Back is directly in the motherboard but front has LoS. Could I just get an extender cable front the back port to the front?

[u/Apprehensive_Mood896 → u/Slaughter_pit]

I have a 3m usb extension from the back of my pc pointing out to my living room.

[u/Slaughter_pit → u/Apprehensive_Mood896]

Seems to work then. Haven't used my frame in 2 weeks since the POS dongle is being a bitch. Might give it a shot. Soon™. Tho I bought a bunch of flatscreen games during the sale so I'm finishing those first. We might even get a steamvr update until then

[u/PatHBT → u/Slaughter_pit]

Easiest solution is to simply try both and use whatever works best.

I don't have frontal usb 3. I plugged it on the back for the time being before seeing if i needed an extensor.

Seems like it works well enough, i guess i won't be needing one.

[u/Pixelplanet5]

the most likely scenario is that the front USB goes through a separate USB controller while the rear ones are direct from the CPU.

[u/Ahris22]

In my experience these issues often comes down to the chassi panel interface using cheaper USB parts than what's on the actual motherboard or the motherboard using cheaper parts for certain inputs.

Labelling the interface as a certain USB standard still leaves room for varying performance as the standard doesn't cover every USB function.