Howard.Spindel@busker.FIDONET.ORG (Howard Spindel) (09/22/88)
> From: akk2@uhura.cc.rochester.edu (Atul Kacker) > Date: 15 Sep 88 20:12:58 GMT > Organization: Univ. of Rochester, Computing Center > Message-ID: <39@ur-cc.UUCP> > Newsgroups: comp.sys.ibm.pc > We have decided to add a large (> 100 Mb) hard disk to one of our > PC-AT's. SInce this is the first time we have contemplated a large > hard disk, we would love to get some feedback from people who have > large hard disks on their machines. The AT is used primarily for > TeX, Ventura Publisher and software evaluations. I installed a Maxtor XT-160 (160mb formatted, ST506 interface) in my AT about six months ago. I have had no problems after getting it installed and am now quite pleased with it. Installation was a problem, as this disk has 1224 cylinders and my (original) AT controller (Western Digital) supported only up to 1024 cylinders, so writes to the higher number cylinders of the disk wound up rewriting the lower numbered cylinders of the disk - two numbers for the same cylinder! Caused lots of grief until I figured it out. Replaced the controller with a new Western Digital and all was well. For partitioning I use the SpeedStor that came with the XT-160 and it works well. -- Howard Spindel - via FidoNet node 1:105/14 UUCP: ...!{uunet!oresoft, tektronix!reed}!busker!Howard.Spindel ARPA: Howard.Spindel@busker.FIDONET.ORG \...!{uunet!oresoft, tektronix!reed}!busker!Howard.Spindel
keithe@tekgvs.GVS.TEK.COM (Keith Ericson) (09/27/88)
In article <29.233DBDD4@busker.FIDONET.ORG> Howard.Spindel@busker.FIDONET.ORG (Howard Spindel) writes:
<
<I installed a Maxtor XT-160 (160mb formatted, ST506 interface) in my AT
<about six months ago... Installation was a problem, as this
<disk has 1224 cylinders and my (original) AT controller (Western Digital)
<supported only up to 1024 cylinders, so writes to the higher number
<cylinders of the disk wound up rewriting the lower numbered cylinders of
<the disk - two numbers for the same cylinder! Caused lots of grief until
<I figured it out. Replaced the controller with a new Western Digital and
<all was well.
<
But last I knew, DOS only know how to count 1024 cylinders, anyway,
so the extra 200 cylinders are either unused or left to another
operating system to access. (We have the same problem with Maxtor
2190's.)
keith
Howard.Spindel@busker.FIDONET.ORG (Howard Spindel) (09/27/88)
> From: keithe@tekgvs.GVS.TEK.COM (Keith Ericson) > Date: 26 Sep 88 17:13:06 GMT > Organization: Tektronix, Inc., Beaverton, OR. > Message-ID: <3995@tekgvs.GVS.TEK.COM> > Newsgroups: comp.sys.ibm.pc r.FIDONEicle <29.233DBDD4@busker.FIDONET.ORG> Howard.Spindel@buskT.ORG > Howard Spindel) writes: < <I installed a Maxtor XT-160 (160mb formatted, ST506 interface) in my AT <about six months ago... Installation was a problem, as this <disk has 1224 cylinders and my (original) AT controller (Western Digital) <supported only up to 1024 cylinders, so writes to the higher number <cylinders of the disk wound up rewriting the lower numbered cylinders of <the disk - two numbers for the same cylinder! Caused lots of grief until <I figured it out. Replaced the controller with a new Western Digital and <all was well. >> But last I knew, DOS only know how to count 1024 cylinders, anyway, >> so the extra 200 cylinders are either unused or left to another >> operating system to access. (We have the same problem with Maxtor >> 2190's.) Yeah, DOS does only know how to count 1024 cylinders, but the Maxtor 2190 came with a special version of SpeedStor which gets around the problem (how I don't know). Anyway, I do get the extra 200 cylinders under DOS - the disk formats to 160mb which I partition as 5 32mb disks. SpeedStor will allow you to create partitions greater than 32mb but I don't use them for fear of compatibility problems with other programs. Actually, the problem was not that DOS only knows about 1024 cylinders - it usually is a BIOS limitation rather than a DOS limitation. -- Howard Spindel - via FidoNet node 1:105/14 UUCP: ...!{uunet!oresoft, tektronix!reed}!busker!Howard.Spindel ARPA: Howard.Spindel@busker.FIDONET.ORG \...!{uunet!oresoft, tektronix!reed}!busker!Howard.Spindel
rac@jc3b21.UUCP (Roger A. Cornelius) (09/28/88)
From article <3995@tekgvs.GVS.TEK.COM>, by keithe@tekgvs.GVS.TEK.COM (Keith Ericson): < In article <29.233DBDD4@busker.FIDONET.ORG> Howard.Spindel@busker.FIDONET.ORG (Howard Spindel) writes: < < < <I installed a Maxtor XT-160 (160mb formatted, ST506 interface) in my AT < <about six months ago... Installation was a problem, as this < <disk has 1224 cylinders and my (original) AT controller (Western Digital) < <supported only up to 1024 cylinders, so writes to the higher number < <cylinders of the disk wound up rewriting the lower numbered cylinders of < <the disk - two numbers for the same cylinder! Caused lots of grief until < <I figured it out. Replaced the controller with a new Western Digital and < <all was well. < < < < But last I knew, DOS only know how to count 1024 cylinders, anyway, < so the extra 200 cylinders are either unused or left to another < operating system to access. (We have the same problem with Maxtor < 2190's.) < < keith But if you use SpeedStor which (probably) came with the Maxtor drive, to do the partitioning (or any of the other large drive partitioning programs available), you can override dos's 1024 cylinder limitation. Roger Cornelius -- +---------- Roger Cornelius -----------+ | (813)347-4399 | | ...gatech!codas!usfvax2!jc3b21!rac | +- ...gatech!usfvax2!jc3b21!rac -+
hlison@bbn.com (Herb Lison) (09/28/88)
I haven't had a chance to play with MS-DOS 4.0, so I don't know if they have solved the problem of large drives. However, I do know that I was able to make use of a Maxtor drive with 280Mb with a SCSI adaptor and software drivers from Future Domain in Tustin California. I was able to treat the entire disk as my D: drive. The Future Domain software creates larger sectors on the drive. If that approach makes sense for your application you should check them out. They stand behind their products. Herb Lison
pete@octopus.UUCP (Pete Holzmann) (09/29/88)
It *is* DOS that can't handle more than 1024 cylinders. You need a device driver that hides the extra cylinders somehow. The most common method seems to be to have a custom device driver (Ontrack=DMDRVR.SYS, Speedstor=HARDRIV.SYS, Adaptec boards come with ADAPTEC.SYS) that can access above 1024 cylinders and make them look like an extra physical disk to DOS. The best and cheapest version I've seen is to get an Adaptec controller of your choice. Its low level format program (built into the ROM BIOS) can handle all this, including download of the device driver onto your disk! Another method is to fake everything up to make it look like there are fewer cylinders. As mentioned elsewhere, Future Domain can use larger sector sizes and act as if there are fewer cylinders (i.e. tell the operating system that you've got a normal number of sectors per track, but actually have only 1/4 as many or whatever, and do the translation on the fly). Personally, I like what some others have done, including Adaptec in their latest BIOS revs: they use normal sector sizes, but you can fake things up so it looks like there are 63 sectors per track; the board does the logical to physical translation on the fly as with the big-sector method. What is nice about this method is that you don't waste a gob of space for each small file on your system, and random record access needn't suffer from pulling in a giant sector when you only need a small chunk of data. Anyway, handling cylinders beyond 1024 is not too big an issue any more, as long as you are using the latest rev levels of SpeedStore, Disk Manager, and most main stream controllers. By the way: the wholesale price on Adaptec 2372 controllers dropped 35-40 bucks recently, presumably due to volume. This should show up real soon in regular pricing, making 1:1 RLL only about 20 bucks more expensive than ST506! Pete -- OOO __| ___ Peter Holzmann, Octopus Enterprises OOOOOOO___/ _______ USPS: 19611 La Mar Court, Cupertino, CA 95014 OOOOO \___/ UUCP: {hpda,pyramid}!octopus!pete ___| \_____ Phone: 408/996-7746
davidsen@steinmetz.ge.com (William E. Davidsen Jr) (09/30/88)
In article <39.23402BED@busker.FIDONET.ORG> Howard.Spindel@busker.FIDONET.ORG (Howard Spindel) writes: | Yeah, DOS does only know how to count 1024 cylinders, but the Maxtor | 2190 came with a special version of SpeedStor which gets around the using the standard AT controller?? | problem (how I don't know). Anyway, I do get the extra 200 cylinders | under DOS - the disk formats to 160mb which I partition as 5 32mb disks. | SpeedStor will allow you to create partitions greater than 32mb but I | don't use them for fear of compatibility problems with other programs. | Actually, the problem was not that DOS only knows about 1024 cylinders - | it usually is a BIOS limitation rather than a DOS limitation. The usual WD controller seems to have only 10 bits for cylinder number... the DOS descriptor field in the DPB has 16 bits. As you say it could be in the BIOS, too. -- bill davidsen (wedu@ge-crd.arpa) {uunet | philabs}!steinmetz!crdos1!davidsen "Stupidity, like virtue, is its own reward" -me
ray@ole.UUCP (Ray Berry) (09/30/88)
The newest version of SpeedStor (vers 5.13, released just last week) allows ROM BIOS override for disks with more than 1024 cylinders. Previous ver- sions did not. A couple of limitations I noted in using the 2372 driver: (1) Each logical drive was limited to 32 mBytes. (2) I couldn't find a disk cache program that would work with the Adaptec driver. I tried Speedcache (distributed by Storage Dimensions), Super-pc-qwik, a well-known and highly respected program from Multisoft in OR, and a cache program supplied by the host pc mfr (Wyse). All refused to recognize the Adaptec driver, and all worked ok with Speedstor. I asked Adaptec Tech support if they knew of any cache programs compatible with their stuff. Drew a big blank. -- Ray Berry KB7HT Seattle Silicon Corp., 3075 112th Ave NE., Bellevue WA 98004 (206) 828 4422 UUCP:...!uw-beaver!tikal!ole!ray =============================================================
Howard.Spindel@busker.FIDONET.ORG (Howard Spindel) (10/04/88)
>From: ray@ole.UUCP (Ray Berry) >Date: 29 Sep 88 23:31:40 GMT >Organization: Seattle Silicon Corporation, Bellevue, WA. >Message-ID: <494@ole.UUCP> >Newsgroups: comp.sys.ibm.pc >The newest version of SpeedStor (vers 5.13, released just last week) allows >ROM BIOS override for disks with more than 1024 cylinders. Previous ver- >sions did not.> >x >A couple of limitations I noted in using the 2372 driver: > (1) Each logical drive was limited to 32 mBytes. > (2) I couldn't find a disk cache program that would work with the > Adaptec driver. I tried Speedcache (distributed by Storage > Dimensions), Super-pc-qwik, a well-known and highly respected > program from Multisoft in OR, and a cache program supplied by > the host pc mfr (Wyse). All refused to recognize the Adaptec > driver, and all worked ok with Speedstor. I am using a Maxtor XT2190 with SpeedStor (subsystem version - a special version that comes with Maxtor disk drives), accessing 1224 cylinders, and I am using it with the SpeedCache program that comes with the system. All works just fine. -- Howard Spindel - via FidoNet node 1:105/14 UUCP: ...!{uunet!oresoft, tektronix!reed}!busker!Howard.Spindel ARPA: Howard.Spindel@busker.FIDONET.ORG \...!{uunet!oresoft, tektronix!reed}!busker!Howard.Spindel