Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watmath!clyde!rutgers!husc6!hao!ames!ptsfa!ski!dr From: dr@ski.UUCP Newsgroups: comp.sys.apple Subject: Re: gs finder and ROM upgrade questions Message-ID: <1922@ski.UUCP> Date: Wed, 11-Nov-87 16:56:14 EST Article-I.D.: ski.1922 Posted: Wed Nov 11 16:56:14 1987 Date-Received: Sat, 14-Nov-87 10:54:18 EST References: <1993@killer.UUCP> <324@n8emr.UUCP> Reply-To: dr@unix.UUCP (David Robins) Distribution: na Organization: Smith-Kettlewell Institute, S.F., CA. Lines: 40 In article <> jockc@killer.UUCP (Jock Cooper) writes: >This is exactly what I did with my old Ramworks //... I bought it with 256k >and bought 768k from MicroProcessors, Inc. I thought I could just move >those chips from the ramworks // to the gsRam. It only worked partially... >The Hitachi chips that came on the Ramworks // worked on the gsRam, but the >768k of Toshiba chips I had previously purchased from Micro... inc. were >reported by the ae memory test as being bad (every one). > >So instead of having 1.5 megs in my machine i have to settle for 768k until >I can figure out why those Toshiba chips dont work on the gsRam, or buy more... gsRAM requires "CAS before RAS" refresh chips. AE supplies Hitachi 50256-15, which are CAS-before-RAS. However, the RAMWORKS cards can use chips that are not of this type, such as the common 41256's. The RAMFACTOR cards require CAS-before-RAS also. I assume the Toshiba chips are not CAS-before-RAS. You must specify that when you order chips. The gsRAM manual has a list of manufacturers and part numbers fore CAS-before-RAS chips. I know the Hitachiis, as well as Mitsubishi, NEC, and Fujitsu. However, these companies may make both types, and one company's numbering scheme may not match. For example, the NEC is "41256", yet it is CAS-before-RAS. The refresh types are not interchangeable. Note that Toshiba makes 1-Meg DRAMs that include CAS-before-RAS, but I guess the 256K one's mentioned above were not. I bought from Jameco Electronics, in Belmont, CA, recently. I talked to their tech person first and found out what they had. They sold me NEC 41256-15, CAS-before-RAS, for $3.25 each. -- ==================================================================== David Robins, M.D. Smith-Kettlewell Eye Research Foundation (previously known as: Smith-Kettlewell Institute of Visual Sciences) 2232 Webster St; San Francisco CA 94115 415/561-1705 (voice) {ihnp4,qantel,dual}!ptsfa!ski!dr The opinions expressed herein do not reflect the opinion of the Institute!