>
> We're happily using the 16-port version of the Cyclades Y-series
> PCI card under NetBSD 1.5.2.   The card also comes in 8- and 32-port
> versions.  I think they may only sell direct; that's how we bought
> ours anyway:
> http://www.cyclades.com/products/svrbas/yseries.php
>

i'm using three 8-port "dump" PCI serial cards at up to 921600 bps and
they work fine making unnoticable slowdown.

at about 160$/each it's CHEAP