Unanswered Topics - Desktops

The Z420/Z620/Z802 use a Texas Instruments  HP USB 3.0  / USB 3.1  (gen 1) card that's based on the TI xHCi controller. 

On my Z420/Z620 machines, the top speed I get across the built in Texas Instruments USB 3.1 gen 1 ports is around 330 MB/s (read), 200 MB/s (write). This is with an NVMe external enclosure that benchmarks around 1000 MB/s read/write across USB 3.1 gen 2 (so the external is capable of full USB 3.1 gen speeds). On other 3.1 gen 1 ports/card (other computers) I can get closer to around 480-500 MB/s with the same enclosure.

I am running the Windows provided driver, 1.0.0.6 which is from 07/17/2015 from Texas Instruments. I am running Windows 10 x64, with the BIOS with defaults. I have tried everything on both the Z420 and the Z620, with the same results. (No surprise, as they effectively use the same motherboard). The Z420 is the Z420 v2 motherboard (2013 boot block).

The sp73254 Intel chipset drivers are installed. I have tried installing the Win7 x64 driver directly from TI (1.16.0) and the sp60962 Zx20 driver from HP (available for Win 7), and in both cases, the driver installs fine, but REDUCES performance. I can find no driver update to improve performance.

So...is the TI chipset just inferior, or is there some special driver that will improve things?

I realize that pushing maximum throughput across the USB 3.0 (3.1 gen 1) interface is something that few people would have had the hardware to test when the Z420 and Z620 were first released. 330 MB/s isn't bad (and is far better than USB 2.0), but it's not great, either, by today's standards. 

Performance of NVMe external USB USB 3 enclosure across the built in USB 3.1 gen 1 TI interfaces on Z620