Today I had time to add in one of the HP Texas Instruments USB 3.0 cards into my Z400, using the Akasa 3.5" form factor front USB 3.0 front ports interface that plugs into the card, and also a Molex 4-wire to SATA power adapter (Molex brand fits best, from Mouser.com). that allows feed of proper amperage of +5VDC to the card to drive the 4 ("2x2") USB3 ports to their specified wattage without risk. There is a 12" Akasa Molex 4-wire extension in there to bring the power from near the DVD down and out to the card plug via the Moles to SATA adapter cable. I have also run these same cards off a floppy power to SATA power adapter, but that feed method offers too low a wattage capacity for full USB3 spec power draw from all 4 ports running at full spec simultaneously.
The card went into the top PCIe port which on these workstations is PCIe Generation II. That slot can handle the bandwidth of the USB3 performance without issue. Drivers are from the Z620 W7Pro64 enterprise list.
So, from the bottom, eSATA adapter; PCI Oxford serial/parallel port card (latest edition) with W7Pro64 drivers from HP that also work on W10Pro64; the 2-slot video card which is a "blower type" of card that exhausts rather than blows around the internal hot air. In that way I don't feel need for adding a front PCI rear-blowing fan, and this thing is very quiet for its very high performance.
Then, the TI based USB3 card with its power feed and 2 ports on the backplane plus a standard header for bringing 2 more USB3 ports forward to the top of the Z400. To the right of that card is the chipset add-on fan from a xw6600 (or a Z600) with a Noctua ULNA 4-wire adapter in-line to drop the unnecessary high speed that HP has set these fans to. Higher up is the Performance heatsink/fan that is the Z400 standard, and finally under that is the X5690 Xeon hexacore that has never been listed in the QuickSpecs for the Z400 but which works great. Standard power supply, not the higher capacity one, and no need for more. It is getting a little tight in there, however.
The front interface for the USB3 access is shown below, as are the backplane and the insides:
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Without the sunlight, inside, the Akasa front face and the HP black plastic parts look very much the same.
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