From owner-freebsd-hardware Mon Nov 23 16:41:42 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id QAA11100 for freebsd-hardware-outgoing; Mon, 23 Nov 1998 16:41:42 -0800 (PST) (envelope-from owner-freebsd-hardware@FreeBSD.ORG) Received: from palrel3.hp.com (palrel3.hp.com [156.153.255.226]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id QAA11082; Mon, 23 Nov 1998 16:41:35 -0800 (PST) (envelope-from darrylo@sr.hp.com) Received: from srmail.sr.hp.com (srmail.sr.hp.com [15.4.45.14]) by palrel3.hp.com (8.8.6 (PHNE_14041)/8.8.5tis) with ESMTP id QAA00407; Mon, 23 Nov 1998 16:41:36 -0800 (PST) Received: from mina.sr.hp.com by srmail.sr.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA066848066; Mon, 23 Nov 1998 16:41:06 -0800 Received: from localhost (darrylo@mina.sr.hp.com [15.4.42.247]) by mina.sr.hp.com with ESMTP (8.8.6 (PHNE_14041)/8.7.3 TIS 5.0) id QAA07352; Mon, 23 Nov 1998 16:41:05 -0800 (PST) Message-Id: <199811240041.QAA07352@mina.sr.hp.com> To: Sam Pigg Cc: chuckr@mat.net, freebsd-hardware@FreeBSD.ORG, smp@FreeBSD.ORG Subject: Re: tyan S1836DLUAN >512Mb problems Reply-To: Darryl Okahata In-Reply-To: Your message of "Mon, 23 Nov 1998 09:21:34 PST." <199811231721.JAA14106@phred.redbacknetworks.com> Mime-Version: 1.0 (generated by tm-edit 1.1.1.1) Content-Type: text/plain; charset=US-ASCII Date: Mon, 23 Nov 1998 16:41:04 -0800 From: Darryl Okahata Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Sam Pigg wrote: > Sorry I didn't mention it, but I have swapped around the simms, and > even got the vendor to provide a new set of 4 256 meg simms. > Symptoms manifest themselves with any combination of simms larger than > 512 Megs (though exactly 512 works fine). [ You mean "DIMMs", not SIMMs". ] Just another possible issue: with the old SIMMs, there was an apparent cottage industry where people would take lots of older (lower- density) memory chips and stuff them onto a board to make a SIMM. The problem with these "lots o'chips" SIMMs was that they'd put a large capacitive load onto the memory bus, with the result that you often couldn't put more than one (pair) into a system. If you did, you ended up with a system that either didn't boot, or crashed intermittently. If you were "lucky", you could "fix" this by tweaking the BIOS to add main memory wait states, but this wasn't particularly nice, as it slowed down the system. The result was that Pentium motherboard manufacturers added comments to their manuals, which basically said not to use SIMMs with more than "N" chips ("N" was something like 18-24 chips -- I don't know, exactly). Now, the question is whether or not there is a similar situation with DIMMs (I don't know, as I'm still stuck in the Pentium I world). If you have DIMMs with "lots o'chips", you might want to see if you can find DIMMs with fewer memory chips. Yes, they'll probably cost much more, but they might be more reliable. -- Darryl Okahata darrylo@sr.hp.com DISCLAIMER: this message is the author's personal opinion and does not constitute the support, opinion, or policy of Hewlett-Packard, or of the little green men that have been following him all day. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message