From owner-freebsd-questions Thu Dec 14 12:29:15 1995 Return-Path: owner-questions Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id MAA08891 for questions-outgoing; Thu, 14 Dec 1995 12:29:15 -0800 (PST) Received: from intele.net (quervo.intele.net [204.118.149.20]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id MAA08880 for ; Thu, 14 Dec 1995 12:29:11 -0800 (PST) Received: (wes@localhost) by intele.net (8.6.12/8.6.5) id NAA02275; Thu, 14 Dec 1995 13:33:32 -0700 From: Barnacle Wes Message-Id: <199512142033.NAA02275@intele.net> Subject: Re: Upgrade - CPU, clock? To: alan@trickler.uu.silcom.com (Alan D. Trombla) Date: Thu, 14 Dec 1995 13:33:31 -0700 (MST) Cc: questions@freebsd.org In-Reply-To: <199512141837.KAA00512@trickler.uu.silcom.com> from "Alan D. Trombla" at Dec 14, 95 10:37:46 am X-Mailer: ELM [version 2.4 PL23] Content-Type: text Sender: owner-questions@freebsd.org Precedence: bulk > Hi, > I am about to upgrade my FBSD 2.0 system to 2.1 and am thinking about > upgrading the hardware as well. > > Currently, I have a Intel 486DX2/66 in a NICE Mini EISA/VLB motherboard > with 16 Meg of RAM (The chips are OKI M514100B-70SJ, so I am guessing > they are 70ns). > > Questions: > 1. What is the fastest chip I can plop into my ZIF socket with no other > changes? A DX4/120, depending on how configurable the motherboard is. Do you have the documentation for the motherboard? If so, check the cpu speed jumpers and see what settings it will allow. Beware that FreeBSD has problems with *some* Cyrix and AMC cpus. > 2. Can I just change the crystal to get a 50MHz system? If so, will > my ATI GUP handle the faster bus? (There are no other VLB boards.) > Is my memory (assuming it *is* 70ns) fast enough? Sure. It'll probably result in a dead system, but you can do that. I know several people who immediately upon recieving DX/2-66s at work changed the clock to 40Mhz. Result: system locked up after 5-6 minutes. A cpu fan on the 486 extended this to 15-20 minutes before locking up. Also, the VL-Bus is very critical about timing; setting the bus speed above 33 Mhz may make your periperhals stop working. If your mother board has switches for VL-Bus at system clocks above 33 Mhz, it'll probably just divide the system clock by two, resulting in a 20 or 25 Mhz VL-Bus. Depending on your video and disk I/O, this may actually slow the system. > 3. Does it make more sense to get a PCI mother board? If you can afford to buy a new VGA card and disk controller, sure. ;^) > In general, I would appreciate any suggestions for squeezing the last > drop of performance out of this system. Chuck it and buy an UltraSPARC? Hey, hey, just kidding! Pentium motherboards are getting pretty cheap now, perhaps it's time to jump? -- Wes Peters | Yes I am a pirate, two hundred years too late Softweyr | The cannons don't thunder, there's nothing to plunder Consulting | I'm an over forty victim of fate... wes@intele.net | Jimmy Buffet