Currently, I'm running what I believe to be the latest control board and card. The USB cable, provided by SB is connected directly into the control card; no serial apater.

The control computer is a rebuild of myself. The motherboard is an ASUS. I get a very good reading (~72-75%) on the communication speed test.

PCI USB adapter, I'm wiling to give that a try. Does price matter much for the piece of hardware? They go from $10 to $75... Something like that would work?

Ground testing... well you know how it is; it can seem to be very good but then... it's electronics... when it test good, what's next to seek for about grounding?!