Page 1:USB 3.0: Dude, Where's My Speed?
Page 2:So, What Makes USB 3.0 Slower Than We Expect?
Page 3:Turbo Mode: Faster USB, With A Caveat
Page 4:USB Attached SCSI (UAS): Enabling Even Better USB 3.0 Performance
Page 5:Enabling UAS On Older USB 3.0-Equipped Motherboards
Page 6:On A Quest For Better USB 3.0 Performance
Enabling UAS On Older USB 3.0-Equipped Motherboards
As we've mentioned, even if you have a UAS-capable device, the system you plug it into must still support the feature before it offers any appreciable benefit. Getting there requires software and hardware considerations.
Addressing The Software Side
Windows 7's driver stack doesn't include UAS support, which is why Asus' USB 3.0 Boost utility includes .inf driver configuration files in a sub-installation folder. These driver configuration files are the missing link.
As it turns out, you can technically use those same drivers to enable UAS support manually. There's one big roadblock in the way, though. When Asus licensed MCCI's UAS driver, it included a subroutine that checks the make and model of your motherboard. If you're not using one of the company's boards, the process becomes prohibitively complex (although we've made it work in our lab).
If, however, CPU-Z identifies the manufacturer of your motherboard as "ASUSTek Computer INC", manually replacing the "USB Mass Storage Driver" with "ASUS USB 3.0 Boost Storage Driver" under System Properties reveals a second "UAS Storage Driver."
Try this on a non-Asus motherboard and you'll get a driver error, unfortunately, and the second driver remains hidden. The only way to work around the error is modify your SMBIOS string using a special tool. Again, it's probably more of an effort than most people want to even bother with, particularly since we aren't even done yet.
To be clear, then, we're only able to proceed with an older Asus board that does support USB 3.0, but isn't already UAS-enabled.
Addressing The Hardware Side
Just because we have the driver installed doesn't mean UAS is working yet. The right hardware matters, too. Take Asus' P8P67 Deluxe as an example. It contains the right SMBIOS string, naturally, but it employs a Renesas USB 3.0 controller, which is why it's not listed on the support page for USB 3.0 Boost. What all of the supported boards do have in common is ASMedia's ASM1042 controller.
The implication is that ASMedia's hardware does offer UAS support, while Renesas' doesn't. We were able to get UAS working through the Z77 chipset's native USB 3.0 ports using Windows 8 on an ASRock's Z77 Extreme6 motherboard (along with the Asus UAS driver on the Z77-equipped P8Z77-V Deluxe), suggesting that Intel's integrated controller does support UAS.
In contrast, the older Renesas controller either lacks the necessary hardware support or it requires a driver update.
The answer, interestingly enough, is to buy a Syba USB 3.0 PCIe card (SD-PEX20112). This cheap solution works because it centers on the ASM1042 controller hardware, which supports UAS, according to ASMedia. Simply install ASM1042 driver from Asus, and you're good to go.
Running Iometer with the Thermaltake BlacX 5G plugged into our Syba USB 3.0 card confirms that UAS works; sequential read speed tops out at 325 MB/s, which is right where we'd expect to see it on a board with native UAS support.