I need to get a different serial port card for two different pieces of test equipment. The on board port I have is buggy.

I did a quick search and found this (also in 4 other places);
http://tldp.org/HOWTO/Serial-HOWTO-19.html

It mostly talks about speed, which really isn't a issue here. I'm mostly interested in compatibility. The test equipment designs are around 10 years old thought one is still being sold. I was told to watch what I buy, to stay away from 'cheaper' chips.

The on board I have now is what is on a Foxconn nVidea N570 chipset MB that uses the stock M$ driver. One device I'm having a issue with corrupted files either being sent or being received. I can't tell. I also don't know if it is the serial port on the PC end or the device end.

Anyway, any suggestions? I see PCI cards as low as $9, while I also see ones for over $100 which I find hard to believe.

What is the difference between these 16C550 that are the cheapos and the more expensive 16550, 16650 & 16950 for over $30 other than the buffer size?

I am using XP Pro w/sp2.

My suggestion...find an old 440BX/PIII motherboard and run 2k on it and network it if you need to get the data to another machine.

Not a chance. This isn't a decicated box for these devices.
Why bother with another MB, case, PS etc. when a other card could/would work. Especially a Wintell chipset. ;)

That's what I'm suggesting...a dedicated box for the beasts, from the era when they were new. Least headaches that way...

I just meant building another computer just to use as storage.