OK, so maybe the D-LInk wifi card was not the solution.  With the D-Link DWA-582 PCIE card there were random system freezes, boot loops and inconsistent speeds instead of the catastrophic failures of the tp-link Archer T9E PCIE card (which made my Dell T1700 unusable).  SO, I went and picked up a Gigabyte GC-WB867D-I adapter that comes with an Intel WiFi card installed in an M.2 socket (on the card) and external antenna.  The M.2 card is actually an Intel 8260 WiFi card so you can use the Intel direct drivers (which I did).  Initially, the card's drivers installed through Windows 10 Pro but I downloaded the most recent drivers from the Intel website.  For the past few days things have been very stable with the connection speed fluctuating between about 433 Mbps and 708 Mbps (I think I've seen as high as 780, but generally it's at 585 Mbps - about 20 ft from the router).  As it's an AC1200 card I would say it's close to max bandwidth which would be 867 Mbps on AC.  All in all I would highly recommend it for stability and compatibility.  Also, I'm assuming that I should be able to safely upgrade to a future generation Intel M.2 WiFi card in the future (limited by two antennas).
Have tried (frustratingly) installing this adapter in a Dell Precision T1700 workstation.  Have tried installing all drivers available (Win XP, 7, 8, 8.1 and 10), both 32 and 64 bit (using Windows 10 Pro 64 bit).  Have tried safe mode, installing from device manager, running compatibility mode on install files, AND I even tried a higher wattage power supply.  At this point I don't know what I haven't tried.  Ultimately the system just locks up or sometimes doesn't even boot up.  Funny thing is that if I leave the antennas off it seems to keep running for some reason. I read somewhere that it is a PCIE X1 type card and it might not be able to handle the X4 slot or X16 slots I tried to install it in.  Frustrated as I've put in way too much time trying to figure this out.  It seems to work fine in my built box - see picture for speed test (AMD processor, etc).  Would recommend except for Dell T1700 of course (and suspect other similar situations). And, yes, I know a USB adaptor would be easier but what are the internal PCIE slots for anyway, decoration?
TP-Link Archer T9E wifi adapter (PCIE) - Can't get it to run after driver 
installation