burleigh@silver.bacs.indiana.edu (Frank Burleigh) (06/22/89)
I've got an IBM PS/2 70-121, a 20mhz 386 with 3 MCA slots. In the 16 bit slot I have an Everex 2400 BPS modem. The other slots are empty. The speaker on the system is NOISY as long as the modem is installed. By that I mean the speaker dribbles sounds inappropriately: in WordPerfect, scolling causes a tiny click at each line; when a line comes in from the comm port, there is a click; displaying fractals with FRACTINT makes it *squeal*; iterative estimation procedures in Micro-TSP cause a "ca-chunk" on each iteration. And I won't even *try* to describe the "Desqview symphony!" For the most part the sound isn't load. But the novelty has certainly worn off, and I want this racket to stop. Now: the modem did not cause problems in my model 80, nor was there any hint of sound when I tried it in a 55SX the other day (also in the 16 bit slot with a video extension). The machine is quiet when the modem is out. I am suspicious about the video system. In general, it sounds to me like an interaction of the video system and the modem, although I have no way to confirm that. My thinking is that the ony 16-bit slot is also the slot with the video extension on it. Like other MCA modems, the Everex uses the MCA's audio line(s). IBM says they know nothing about this; Everex has "no reports" and the modem "works fine in ours." The fact that the system board "works" fine without the modem suggests the modem is the problem, except that I can't get noise on other machines with that same modem, which suggests a subtle problem with either my particular system board or the 20mhz model 70 in particular. Can anyone suggest: (1) an interpretation of this problem; and (2) how I can get one of these two companies to take responsibility for finding the problem? (Yanking the speaker is not an acceptable solution.) Thanks in advance for your thoughts. Frank Burleigh burleigh@silver.bacs.indiana.edu USENET: ...rutgers!iuvax!silver!burleigh BITNET: BURLEIGH@IUBACS.BITNET Department of Sociology, Indiana University, Bloomington, Indiana 47405