are messages like that normal in logs? Jul 17 19:15:31 chylonia kernel: sio2: 681 more interrupt-level buffer overflows (total 101746) with NetBSD i've got similar too but very very rare, now i'm getting every 10-20 seconds. anyway - ftp speeds doesn't look much slower. chip is 16550A on ISA cards with 8x multiply, used at real 230400 baud.