Problems with screen to serial usb on F17

[Robert Moskowitz]

I have an old F17 Asus Eee700 and trying to hook it to a USB TTL UART as 
a serial console to some armv7 systems using screen:

screen /dev/ttyUSB0 115200

I am getting garbage characters.  Not all the time, but particularly at 
the beginning.  I don't see this on either of my two F20 systems:  
Lenovo x120e and Asus Eee900.

I can't easily upgrade this Eee700 and I would be happy just using F17 
screen.  But is this likely to be OS or hardware?