Ethernet over PCI may perform better than Ethernet over USB in an old system, as USB doesn't do DMA and is CPU-bound.

USB 3.0, though, will be most likely a complete waste of time and space; even if you get it to work via the adapter, I doubt you'll get substantially higher speeds than USB 2.0.

dr_st wrote:

Ethernet over PCI may perform better than Ethernet over USB in an old system, as USB doesn't do DMA and is CPU-bound.

USB 3.0, though, will be most likely a complete waste of time and space; even if you get it to work via the adapter, I doubt you'll get substantially higher speeds than USB 2.0.

Totally get what you're saying about hit in ethernet speed.

As far as USB 3.0 being a waste, I'm not so sure.

PCI bus has a theoretical max of 133 MB /s (megabytes, not bits) which equates to 1.064 Gbit of data.

USB 2.0 max is 480 Mbit /s (bit not byte)
USB 3.0 max is 5 Gbit /s

So I would expect a PCI bus limited USB 3 to still be roughly twice as fast as USB 2.0 no?

I'm aware of the theoretical numbers, but in practice everything can be pretty far from theory. First, USB (any USB) never reaches anything close to its theoretical numbers in sustained speeds. It is usually 30% to 50% lower. Second, PCI bus speed is spread between every PCI device in your system. Finally, as I mentioned, USB is CPU-bound, and the slower the CPU, the lower the performance, not to mention the losses due to the adapter.

Of course, the only real way to know is to test it, and I can't find test results for USB 3.0 on such old systems. Maybe you can try and contribute to the community knowledge. 😀

dr_st wrote:

I'm aware of the theoretical numbers, but in practice everything can be pretty far from theory. First, USB (any USB) never reaches anything close to its theoretical numbers in sustained speeds. It is usually 30% to 50% lower. Second, PCI bus speed is spread between every PCI device in your system. Finally, as I mentioned, USB is CPU-bound, and the slower the CPU, the lower the performance, not to mention the losses due to the adapter.

Of course, the only real way to know is to test it, and I can't find test results for USB 3.0 on such old systems. Maybe you can try and contribute to the community knowledge. 😀

Very good points! Since I already have the hardware I may add well give it a go.

My OCD wants functioning front blue USB ports on this thing which are faster than the white ports so hopefully I can get it set up properly. Tonight or tomorrow I'll finish Frankensteining the PSU together and should be able to get the rig set up at least for some testing

Its almost pointless to argue the speed of a USB interface, when sneakerneting files. So I can't intellectually entertain the conversation.

https://en.wikipedia.org/wiki/Sneakernet

Warlord wrote:

Its almost pointless to argue the speed of a USB interface, when sneakerneting files. So I can't intellectually entertain the conversation.

https://en.wikipedia.org/wiki/Sneakernet

Hmm in the instance of a retro PC so old that it only includes USB 1.1 ports, file transfer speed improvement by adding USB 2.0 or hopefully 3.0 seems intellectually relevant 😉

Find usb stick
walk to computer
insert usb
walk to chair
copy pasta
walk to computer
pull out usb
walk to other computer
insert usb
walk to chair
copy pasta

This is your transfer speed. + whatever the speed of the usb interface.

_________________________________________________________________

Transferering over internet
Copy pasta
done

Warlord wrote:

Find usb stick walk to computer insert usb walk to chair copy pasta walk to computer pull out usb walk to other computer insert […]
Show full quote

Find usb stick
walk to computer
insert usb
walk to chair
copy pasta
walk to computer
pull out usb
walk to other computer
insert usb
walk to chair
copy pasta

This is your transfer speed. + whatever the speed of the usb interface.

_________________________________________________________________

Transferering over internet
Copy pasta
done

If you're talking about a small amount of data to copy /paste yes definitely trivial, but a few gb or more and you will really notice being stuck with USB 1.1 I promise 😀

Tbh even on USB 3.0 things can take a while. Recently I was configuring a tiny 256gb SanDisk USB drive for a Playstation Classic and it took about 8 hours to write 220gb from a SATA ssd in the desktop.

8 hours for 220gb? That's an average speed of about 8MB/s? That's way too slow even for USB 2.0. A lot of the cheap USB 3.0 flash drives have high read speeds but really low write speeds.

dr_st wrote:

8 hours for 220gb? That's an average speed of about 8MB/s? That's way too slow even for USB 2.0. A lot of the cheap USB 3.0 flash drives have high read speeds but really low write speeds.

Yep needless to say I switched to a better drive. I think the tiny SanDisk was overheating.