Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!sample.eng.ohio-state.edu!purdue!haven.umd.edu!mimsy!dftsrv!oneel From: oneel@heawk1.gsfc.nasa.gov ( Bruce Oneel ) Newsgroups: comp.sys.ibm.pc.misc Subject: Re: please tell me how to co-install RLL & MFM hard drives....PLEASE! Message-ID: Date: 15 May 91 13:09:15 GMT References: <76334@eerie.acsu.Buffalo.EDU> Sender: news@dftsrv.gsfc.nasa.gov Organization: STX/GSFC Nasa Lines: 37 In article chchoi@eng.auburn.edu (Cheong Hyeon Choi) writes: In article <76334@eerie.acsu.Buffalo.EDU> v087mxgb@ubvmsa.cc.buffalo.edu writes: >I have a type 2 - 20 Mb MFM hard drive installed (works fine) > >I received a 30 Mb RLL drive FREE!!! and want to use both > >Ive heard that I can, but how do I do this....both have a >controller card for my 286 machine, how do I partition them >and set one as drive 0 and one as drive 1, etc.... > Hi. Yes, I had the same experience. In this case, you try to format MFM drives as RLL if your two MFM drive is products of Seagate. After that, you are getting more disk capacities. With my experience, there had been no problem. But I don't know exactly why it works but very fine. As I know, the capacity of the MFM drive is going to increase by 50%. Do it. Choi` Well, you can reformat your MFM drive as RLL, but, it might not work as well as you want it to. Most newer MFM drives really aren't "certified" to run RLL. As an example, a ST238 (30 or so meg, seagate RLL drive) is the same as a ST225 (20 or so meg, seagate MFM drive). (I may have the numbers wrong, but the idea is right). They're the same things, but, the st238 has passed tests showing that it will work with the higher densities of RLL. Sure, the 225 will low level format to 30 or so meg with an rll controller, but you may get errors later (or sooner). It's up to you. The reason why there is about a 50 % increase in the disk space is that MFM is 17? sectors per track and RLL is 26? sectors per track. bruce -- Bruce O'Neel oneel@heasfs.gsfc.nasa.gov NASA/GSFC/STX/Code 664