Using USB Loopback plug w/ Burn in test

[stinkfoot_e92]

Good Evening,

My name is Anthony and I am a support technician @ sourcecode.com. I'm looking for some expertise in proper usage of the loop back plug to diagnose USB issues.

To my understanding I have the option of using the USB2Test software provided or using the option to integrate it into burn in test in which we use the most here.

I've manually installed the drivers and verified it in device manager but its not being detected in burn in test. I've swapped usb cables,swapped usb dongles,insured drivers are properly installed no luck getting it to work with burn in test.

Also what is proper way of using USB2Test? I see alot of options to enable im not quite sure which ones to choose.

-Thanks

[Tim (PassMark)]

If you open the BurnInTest test preferences and go to the USB tab (where you can set the number of USB plugs to test) there should be a list of detected USB plugs, is it not being displayed here? Have you selected the USB test to run under "test selection and duty cycles"?

There is a help file included with USB2Test to explain the settings in more detail but to paraphrase; the loopback test can used to verify data can be sent between the USB plug and the computer without error (same test mode used in BurnInTest) while the benchmark test can be used to check the maximum speed between the USB plug and the computer.

[stinkfoot_e92]

Typically, how long should I run the the loopback test in USB2Test on the suspected usb ports?

[David (PassMark)]

If it works for even 1 minute the probably is very high that it is functioning correctly.
In rare cases you might get intermittent problems that take some hours to manifest themselves.

[stinkfoot_e92]

Theoretically I know usb 2.0 is rated at 480Mb/s. In the lookback test I am seeing a speed of 360 (read) and 262 (write).

With these results how can I determine if the ports are performing to specification? What numbers should I expect to see on the loopback benchmark.

Thanks.

[David (PassMark)]

In the lookback test I am seeing a speed of 360 (read) and 262 (write).

This is pretty much normal for USB2.

Both the USB2 and USB3 plugs have a loopback mode and a benchmark mode. Only the benchmark mode will get near the theoretical speed of USB2/3. But there are a lot of overheads in the USB standard with the encoding scheme, header, checksums and polling, etc... So real data throughput can never reach the theoretical quoted speed.

[stinkfoot_e92]

I figured. Would you have any other advice in properly diagnosing usb ports? I really appreciate you taking the time and assisting me. We use alot of Pass Mark products here.