Xref: utzoo unix-pc.general:882 comp.sys.att:3569 comp.periphs:1029 Path: utzoo!utgpu!water!watmath!clyde!att!mtunx!icus!lenny From: lenny@icus.UUCP (Lenny Tropiano) Newsgroups: unix-pc.general,comp.sys.att,comp.periphs Subject: UNIX pc fan 27CFM vs. 34CFM and 12VDC vs. 120VAC? Keywords: fan, hot, memory Message-ID: <401@icus.UUCP> Date: 23 Jun 88 01:48:47 GMT Organization: ICUS Software Systems, Islip, New York Lines: 57 About 4 months ago I replaced my *DEAD* UNIX pc fan with a Radio Shack 12VDC 27CFM (cubic feet/minute) 3.5" look-alike. Back then I didn't have any problems, but just recently I'm experiencing sporatic memory parity errors. Diagnostics show nothing, although I think I am attributing it to the extreme heat and humidity my bedroom is experiencing. A little about my configuration: 67MB 3B1 with 3.0MB RAM (1 dual EIA w/1.0MB on the board) DOS-73 board two Radio Shack 3.5" 27CFM 12VDC fans A little about my problem and a few questions: ... NMI (parity error) at 0x2FFAC8 (*hpte: 0xE17B) Wed Jun 22 15:00:07 1988 NMI (parity error) at 0x84298 (*hpte: 0x412F) Wed Jun 22 17:52:22 1988 NMI (parity error) at 0x84298 (*hpte: 0x412F) Wed Jun 22 17:52:28 1988 NMI (parity error) at 0x84298 (*hpte: 0x412F) Wed Jun 22 17:53:02 1988 NMI (parity error) at 0x82200 (*hpte: 0x4169) Wed Jun 22 19:05:11 1988 Problem didn't exist in cool weather even with the EIA/RAM expanded memory. Problem didn't happen [as often] with EIA/RAM board out. Machine is running 24 hrs/day 7 days/wk. Programs die with "Memory fault - core dumped" (signal 8) when the NMI parity error occurs. (as suspected) All socketed memory is seated tight. Boards get very hot, does this effect memory? Addresses vary from low 0x80000 to high 0x2FFFFF (does the lower addresses correspond to physical location of memory or just where the program is at that time which can be on either the motherboard memory or expanded memory? Was the 3B1 original fan a more output (ie. 34CFM) and maybe it is not pulling enough cool air? How does the heat and humidity affect the operation? Will air conditioning alliviate this? What does "(*hpte: 0x4169), etc..." mean? Using the "s4test" expert mode can I run the memory parity test on a particular segement is a "SOAK" mode where I it will run over and over on that test? Sort of related question... Has anyone tried the 120VAC fan instead of the 12VDC fan and reduce the strain on the power supply? Does the AC hum interfere with any operation? Thanks for any help, Lenny -- US MAIL : Lenny Tropiano, ICUS Software Systems IIIII CCC U U SSS PO Box 1 I C U U S Islip Terrace, New York 11752 I C U U SS PHONE : (516) 968-8576 [H] (516) 582-5525 [W] I C U U S TELEX : 154232428 [ICUS] IIIII CCC UUU SSS AT&T MAIL: ...attmail!icus!lenny UUCP : ...{talcott, boulder, pacbell, sbcs, mtune, bc-cis}!icus!lenny