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USB Net Speed Estimator



there is an interesting UAS/UASP article at on tom's hardware.

The ASMedia xCHI ASM1042A USB Host Controller chip, not the ASMedia XHCI ASM1042 USB 3.0 host controller chip, and thus not the syba controllers support UAS.

ASUS USB 3.0 Boost drivers caused flakiness (this may get fixed later), and the USB firmware update tool v2 maybe bricked my USB 3.0 firmware apparently or the update software is just buggy and it doesn't work. support says I need to have my motherboard replaced (but I need my system too much). funny, my usb 3.0 seems to be working, because I can still type and use my mouse, and my floppy drive works, and hard drives work - the firmware update tool was probably just buggy/broken. I hope a BIOS update fixes this, it could. anandtech forum posts on ASMedia firmware updates

hard drives appear and disappear with the Boost driver I am using in win7. so I uninstalled it or just turned boost off and things became more stable I think.

USB Net Speed Estimator


Use estimated overhead ratios instead of Actual bps"/"Rated bps" and other boxes below
Use "Actual bps"/"Rated bps" boxes only
(Examples: 10.12:Mbps, 10.12:Gbps, 10.12:Tbps, 10.12:MBps, 10.12:GBps, 10.12:TBps)
(Examples: 10.12:Mbps, 10.12:Gbps, 10.12:Tbps, 10.12:MBps, 10.12:GBps, 10.12:TBps)
(fraction or math or floating point value accepted. if encoding is 8b10b, put in 8/10 (for USB 3.0 and under). if encoding is 128b132b (USB 3.1) put in 128/132 and if you have a floating point(real) value put it in instead. can take math using math.js.put in 1 to ignore) Example:
(fraction or math or floating point value accepted. can take math using math.js. put in 1 to ignore) Example:
(values from here)

gross physical speed:
net speed estimate:
encoding ratio:
overhead ratio: (multiplies by estimated ratio and UAS to get efficiency)
UAS/UASP ratio: (multiplies by estimated ratio and encoding to get efficiency)

UAS/UASP-capable controller cards
should work with ASUS USB 3.0 Boost driver (MCCI), ASRock USB 3.0 driver - note - the SYBA controller in the article has the wrong chip.
for MAC
UAS/UASP-capable motherboards (driver only?):
usb support on ASUS has been flaky with USb 3.0 Boost driver, with drives disappearing and reappearing, a BIOS update may fix this, or the update may be using a separate utility.
article attribution/references
I did not use this article. but it's technically interesting, but about usb 2.0
usb 3.1 uses 8b10b encoding. there may be additional overhead outlined in the 1.1 stuff, but they did overhaul the protocol, so unsure now.