Thanks for the tips - hope to become self sufficient shortly 
One last thing I hope - my Lime is showing up as a USB2 device, when plugged into a new Orinco 3.1 pci-e adapter.
LimeUtil --find
- [LimeSDR-USB, media=USB 2.0, module=STREAM, addr=1d50:6108, serial=0009060B00471F23]
I just plugged in a 3.0 Thumb drive and it shows as 5000M but the Lime is still 480M:
Plugin LimeSDR - device 9:
Feb 8 18:40:37 compute1 kernel: [87719.816918] usb 3-1: new high-speed USB device number 9 using xhci_hcd
Feb 8 18:40:37 compute1 kernel: [87719.816944] xhci_hcd 0001:58:00.0: ERROR: unexpected command completion code 0x0.
Feb 8 18:40:37 compute1 kernel: [87720.038792] usb 3-1: New USB device found, idVendor=1d50, idProduct=6108
Feb 8 18:40:37 compute1 kernel: [87720.038807] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Feb 8 18:40:37 compute1 kernel: [87720.038814] usb 3-1: Product: LimeSDR-USB
Feb 8 18:40:37 compute1 kernel: [87720.038820] usb 3-1: Manufacturer: Myriad-RF
Feb 8 18:40:37 compute1 kernel: [87720.038826] usb 3-1: SerialNumber: 0009060B00471F23
Feb 8 18:40:37 compute1 mtp-probe: checking bus 3, device 9: “/sys/devices/pci0001:40/0001:40:0f.0/0001:58:00.0/usb3/3-1”
Feb 8 18:40:37 compute1 mtp-probe: bus: 3, device: 9 was not an MTP device
Then plugin Thumb Drive - device 2:
Feb 8 18:47:51 compute1 kernel: [88154.252429] usb 4-2: new SuperSpeed USB device number 2 using xhci_hcd
Feb 8 18:47:51 compute1 kernel: [88154.272283] usb 4-2: Parent hub missing LPM exit latency info. Power management will be impacted.
Feb 8 18:47:51 compute1 kernel: [88154.278270] usb 4-2: New USB device found, idVendor=05dc, idProduct=a82a
Feb 8 18:47:51 compute1 kernel: [88154.278282] usb 4-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Feb 8 18:47:51 compute1 kernel: [88154.278290] usb 4-2: Product: USB Flash Drive
Feb 8 18:47:51 compute1 kernel: [88154.278295] usb 4-2: Manufacturer: Lexar
Feb 8 18:47:51 compute1 kernel: [88154.278301] usb 4-2: SerialNumber: AAYSZK37H9Z6BZWN
Feb 8 18:47:51 compute1 mtp-probe: checking bus 4, device 2: “/sys/devices/pci0001:40/0001:40:0f.0/0001:58:00.0/usb4/4-2”
Feb 8 18:47:51 compute1 mtp-probe: bus: 4, device: 2 was not an MTP device
lsusb shows them:
root@OSCompute1:~# lsusb -t
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M
|__ Port 2: Dev 2, If 0, Class=Mass Storage, Driver=usb-storage, 5000M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 480M
|__ Port 1: Dev 9, If 0, Class=Vendor Specific Class, Driver=, 480M
Unplug and switch them in the 2 ports, and the LimeSDR-USB is now high-speed USB device number 10, and the thumb drive is new SuperSpeed USB device number 3 using xhci_hcd:
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M
|__ Port 1: Dev 3, If 0, Class=Mass Storage, Driver=usb-storage, 5000M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 480M
|__ Port 2: Dev 10, If 0, Class=Vendor Specific Class, Driver=, 480M
Doing the SoapySDRUtil rate test looks like the limit is about 11e6 SPS:
SoapySDRUtil --args=[“driver=lime”] --rate=8e6 --channels=“1” --direction=“RX”
Begin RX rate test at 8 Msps
Starting stream loop, press Ctrl+C to exit…
L 1057740
7.9168 Msps 31.6672 Bps
7.95839 Msps 31.8335 Bps
7.97245 Msps 31.8898 Bps
SoapySDRUtil --args=[“driver=lime”] --rate=10e6 --channels=“1” --direction=“RX”
Begin RX rate test at 10 Msps
Starting stream loop, press Ctrl+C to exit…
L 1052640
9.89614 Msps 39.5846 Bps
9.94806 Msps 39.7923 Bps
9.96537 Msps 39.8615 Bps
SoapySDRUtil --args=[“driver=lime”] --rate=15e6 --channels=“1” --direction=“RX”
Begin RX rate test at 15 Msps
Starting stream loop, press Ctrl+C to exit…
L 1456560
10.8664 Msps 43.4655 Bps
10.9302 Msps 43.7208 Bps
10.946 Msps 43.7839 Bps