Path: utzoo!utgpu!watmath!clyde!bellcore!rutgers!ucsd!ucbvax!VAX.FTP.COM!jbvb From: jbvb@VAX.FTP.COM (James Van Bokkelen) Newsgroups: comp.protocols.tcp-ip.ibmpc Subject: ethernet card portability Message-ID: <8812080058.AA05309@vax.ftp.com> Date: 8 Dec 88 00:58:49 GMT References: <8812062152.af22648@Obelix.TWG.COM> Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 19 In general, a PC-bus (8-bit slot) card will run in all machines. A 16-bit slot card usually requires an AT (but 3Com's 3C505 will go 16-bit on an AT, but runs in an 8-bit slot on PCs). There are two classes of potential problems: Some cards aren't fast enough to deal with fast (>6Mhz) busses. Early U-B NIC cards were this way, but they've fixed it. Another problem is drivers that contain timing loops on very fast processors (regardless of bus speed). There are a few cards out there (usually with on-board processors) which require waits in the driver that can't be done with clock interrupts (they take too long and the card times out). This problem may be software-vendor-dependent, too. The 3C503 and the WD8003 should work in all the machines you mention. One of the advantages of the MCA bus is that it is supposed to be sufficiently well specified that the clock rate problems I mention above can't happen, but you can still get the timing loop problem.... James VanBokkelen FTP Software Inc.