USB 3.0 Wireless Adapters VS PCI-Express Adapters

[sunil.gulabani]

Hi just wanted to know if anyone has ever tested two equally comparable PCI-E Wireless adapter VS its usb 3.0 counterpart.. which is faster...

e.g. PCE-AC56 compared to USB-AC56..

these are from asus I am sure other companies too have such products.. Just want to know will there be a difference in how these devices function on a desktop..
Similar conditions of usage..

 

[thiggins]

No, we haven't done such a test. But bus speed isn't a limit for 2x2 devices. USB 2.0 even has sufficient bandwidth.

PCIe devices are more limiting in terms of antenna placement to obtain optimum signal.

 

[RogerSC]

I was looking at the PCE-AC68, and it looked like the antenna was on a cable, like the USB adapters sometimes are. So it seemed like it there would be a comparable degree of freedom for positioning the antenna to a USB adapter. Depending, of course, on how one's desktop system is positioned. I realize that some of the PCI Express adapters have the antennas fixed on the external part of the card, which would be at the back of the computer then, but that's much less interesting to me.

I'm hoping that was really the case, or was it artistic freedom in the ad *smile*?

 

[sunil.gulabani]

No, we haven't done such a test. But bus speed isn't a limit for 2x2 devices. USB 2.0 even has sufficient bandwidth.

PCIe devices are more limiting in terms of antenna placement to obtain optimum signal.

the USB 3.0 device apparently is 2x2 device but the pci-e device is 3x3

 

[thiggins]

the USB 3.0 device apparently is 2x2 device but the pci-e device is 3x3

The original question was about an equal comparison, i.e. two 2x2 devices.

 

[thiggins]

I was looking at the PCE-AC68, and it looked like the antenna was on a cable, like the USB adapters sometimes are. So it seemed like it there would be a comparable degree of freedom for positioning the antenna to a USB adapter.

A USB cable can be much longer than an antenna cable, with no sacrifice of signal strength. You get the most placement flexibility by using a wireless bridge since it connects via Ethernet.

 

[azazel1024]

No, we haven't done such a test. But bus speed isn't a limit for 2x2 devices. USB 2.0 even has sufficient bandwidth.

PCIe devices are more limiting in terms of antenna placement to obtain optimum signal.

It would depends on the adapter if USB2 was a limitation. Ideal bus speed is 480Mbps, but maximum with overhead is in the area of 320-340Mbps. I can deffinitely get a lot more than that with my Intel 7260ac and my Archer C8 (about 480-490Mbps absolute max in a very ideal situation, but I can regularly get 400Mbps with a good connection resonably close to the router).

That said, with a 5Gbps protocol speed and roughly 4.2-4.5Gbps after overhead is accounted for...USB3.0 is not going to be any kind of limitation. What probably is, is the design. Looking at it, most USB3.0 designs are designed for a laptop, so they are physically fairly small adapters and often have relatively small antennas, in comparison to PCI-e adapters which tend to have larger antennas and often have big board area (which means larger and possibly higher quality components can be used).

At a guess, most good PCI-e adapters are going to be at least somewhat better than most good USB3.0 adapters. I am undoubtly sure exceptions exist to that guideline. Oh, also if it matters to you, PCI-e has significantly lower latency than USB3.0 does. Now, this likely won't matter for networking, but there is going to be a different of at least hundreds of microseconds...which probably only matters if you are doing something like using iSCSI for executing programs as if on local storage and in this case, with the latency of wireless, it would likely suck anyway, but the difference might still make a little difference to you (the latency difference is going to be WAY too low to be preceivable in online gaming, we are talking likely less than a 1ms difference).

 

[azazel1024]

A USB cable can be much longer than an antenna cable, with no sacrifice of signal strength. You get the most placement flexibility by using a wireless bridge since it connects via Ethernet.

THIS can often be a deciding factor though. If placement isn't a controlling factor, PCI-e is likely to be better, but because you can place the adapter and antennas, say, on your desk instead of hiding behind your tower under your desk, this can increase the wireless signal significantly, which likely will more than make up for any mild to moderate differences in the ability of the adapter itself. If placement isn't an issue though...PCI-e.

Especially if comparing mini-PCIe internal laptop adapters to ones stuck in the USB port, PCIe > USB almost everytime (for equivelent speed class).

 

[stevech]

or use a wifi bridge with x ft. of cat5 to the pc.