It's doesn't HAVE TO BE a USB to Serial cable does it? Our Dell D810 has a real serial port on it.
I know all about USB to Serial converters. I have my own design. I use a FTDI USB serial chip to handle the RS-232.
Other cables for reference...
http://www.plccables.com
bottom line, no problems.
I am using the FTD FT232BM chips.
http://www.ftdichip.com/Products/FT232BM.htm
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