kevin@neptune.AMD.COM (Kevin Tomasek) (09/21/89)
With all this hard drive controller action going on and running out of disk space myself, I looked into some RLL controllers and larger disks. One person who claimed to work for a smaller pc maker said they had evaluated all the RLL controllers available. ( 1-2 yrs ago) They were unable to qualify any of them.. With that info I looked for the next largest disk available in MFM (40MB to 80MB). I called a couple of those hard drive mail order joints for prices and a couple of them suggested that if I change disks I should switch controllers to a pure scsi controller. Claiming addition drives can be daisy chained without a problem. The prices for an 80mb drive and scsi controller were very competitive with any other controller. Any comments or specific experience... Thanks for any info.. kevin -- ************************************************************************* Kevin Tomasek kevin@neptune.amd.com AMD - Advanced Micro Devices, Austin, Tx (512)462-5381 *************************************************************************
dregis@pldote.intel.com (~Dave Regis) (09/22/89)
>suggested that if I change disks I should switch controllers to a pure >scsi controller. Claiming addition drives can be daisy chained without >a problem. The prices for an 80mb drive and scsi controller were very >competitive with any other controller. > >Any comments or specific experience... My 386 system is configured with a Seagate ST-01 SCSI controller and an ST277N disk. The 277N and 277R mechanisms are the same as far as I know; obviously the drive controller board is different. Since the installation, I've had ZERO problems as far as failures or in- compatibilities. A point to consider: SCSI drives have two ways of being addressed. There are hardware jumpers and the is also a software address built onto the drive. The drive I have was originally on a Mac and the software address was set to 3 (three). When I yannked from the make and hooked it up the the PC, the ST01 wouldn't see any devices on the bus (SCSI); the firmware only recognizes devices zero (0) and one (1). The tricky part is that this drive can be set to be recognized by its software or hardware address; on my Mac, I use software addresses as it makes it much easier to reorder the disks. I fought with the darn thing for two weeks twiddling the cable, jumpers, etc, until the realization hit me. I then hooked back up to my Mac, set it for hardware addressing, hooked it up the PC, and WOW it worked. I had made several calls to Seagate who claimed the controller must be bad -- they hadn't suggested the addressing mode! It probably won't be an issue unless the drive had been Mac-ed at some time during its life. Also: As delivered, the ST01 (probably ST02), only recognizes the devices addressed as 0 and 1. Seagate claims that drivers can be written to allow upto 7 devices on the bus - I've seen it done. Overall performance has been good. I don't have any disk benchmarking programs that give avg seek time and data throughput rate, so I can't give you any figures. I can say that it is WAY quicker than the ST225(N). Hope this helps... Dave Regis nosig
karl@ddsw1.MCS.COM (Karl Denninger) (09/22/89)
>Item 5678 (1 resps) by kevin at neptune.AMD.COM on Fri 22 Sep 89 04:35 >[Kevin Tomasek] Subject: SCSI hard drive controllers.. >(24 lines) > >With all this hard drive controller action going on and running out of >disk space myself, I looked into some RLL controllers and larger disks. > >One person who claimed to work for a smaller pc maker said they had >evaluated all the RLL controllers available. ( 1-2 yrs ago) They >were unable to qualify any of them.. With that info I looked for the .... That is simply not true anymore. We have qualified the WD1006V/SR2 boards a while back (about 6-7 months), and we build PCs. Out of some 60-70 boards, I have had one bad one. It failed within the first two weeks, and was immediately replaced. None of the others have given anyone trouble. There are some drives which fail to work with these things; if you try using it with an MFM drive it may or may not work. RLL-qualified drives have all worked to date, and none have failed (so far). The 1006 is also a track-cache board, and incredibly fast. It will also tolerate a 16 Mhz bus clock, so you can tell your system to run the 16-bit bus at 0 wait states (if your BIOS supports this option). The 1006 will also remap drive types internally so you don't have to fight the drive tables in your machine. Note, however, that the remapping will NOT work for drives with > 1024 cylinders. SCO Xenix doesn't care; simply turn off the bios and use the formatter we provide. 386/ix, on the other hand, will choke. For MSDOS this is not much of an issue. All in all, quite a nice board and cheap too. We sell 'em for $179. For the performance you get they're hard to beat; I/O speeds approach 700KB/second depending on your I/O bus capabilities (I've seen anywhere from 550KB/sec to 690KB/sec). -- Karl Denninger (karl@ddsw1.MCS.COM, <well-connected>!ddsw1!karl) Public Access Data Line: [+1 312 566-8911], Voice: [+1 312 566-8910] Macro Computer Solutions, Inc. "Quality Solutions at a Fair Price"
JLI@kuhub.cc.ukans.edu (09/23/89)
In article <[251a3461:5678.2]comp.ibmpc;1@ddsw1.MCS.COM>, karl@ddsw1.MCS.COM (Karl Denninger) writes: >>Item 5678 (1 resps) by kevin at neptune.AMD.COM on Fri 22 Sep 89 04:35 >>[Kevin Tomasek] Subject: SCSI hard drive controllers.. > > We have qualified the WD1006V/SR2 boards a while back (about 6-7 months), > and we build PCs. Out of some 60-70 boards, I have had one bad one. It > failed within the first two weeks, and was immediately replaced. We are using the WD1006V/SR2 a lot, mostly with the Mitsubishi MR535 (I could be wrong about the model number), the 65MB(RLL)/40MB(MFM) drives. It indeed has a very low failure rate, compare with the ones we used to use (such as the DTC 7287). However, we had a lot of problem with the combination of WD1006V/SR2 and Miniscribe 8450 (40MB RLL, 771 Cyl. 4hd.). Does anyone encounter this problem? The common problem is that the bad sectors keeps increasing (slowly at first, and after a few weeks it grows faster and faster). After reformating the drives, the newly appeared bad sectors are gone, but they are coming back soon. We have specially recorded a few of such cases, the bad sector locations seemed to be complete random. It is very frustrating, almost 95% of such combinations we installed (in different kind of machines, DTK, Zenith, IBM AT, etc.) were returned to us within two months of installation with the same problem (if we only installed a few of them, we may consider unlucky. But up to 200 units? It's just too much!). > None of the others have given anyone trouble. There are some drives which > fail to work with these things; if you try using it with an MFM drive it may > or may not work. RLL-qualified drives have all worked to date, and none > have failed (so far). > We also use WD1006V/SR2 with Seagate drives (277R, 4144R), and have not found any problems yet. > The 1006 is also a track-cache board, and incredibly fast. It will also > tolerate a 16 Mhz bus clock, so you can tell your system to run the 16-bit > bus at 0 wait states (if your BIOS supports this option). The 1006 will > also remap drive types internally so you don't have to fight the drive > tables in your machine. Note, however, that the remapping will NOT work for > drives with > 1024 cylinders. SCO Xenix doesn't care; simply turn off the > bios and use the formatter we provide. 386/ix, on the other hand, will > choke. For MSDOS this is not much of an issue. > The on-board BIOS is nice, and it also provide user defined drive configuration capability (Type 1), so you can use some odd drives if the operating system is MS-DOS. We haven't tried SCO Xenix with it yet, but as far as we know, the Novell Network would not like the on-board BIOS. > All in all, quite a nice board and cheap too. We sell 'em for $179. For > the performance you get they're hard to beat; I/O speeds approach > 700KB/second depending on your I/O bus capabilities (I've seen anywhere from > 550KB/sec to 690KB/sec). > This board is fast. I have one in my computer (386/25MHz) at home, with a Mitsubishi 65MB drive. With the DOS 4.01's smartdrive installed, the reported disk performance index (Norton 4.51) is 9.6. By the way, we also have an unsolved problem with Seagate SCSI drives. Every one of these drives (3.5" 20MB) we installed in past 12 months had the same problem, i.e. very slow access time and sometimes won't boot. We have sent them back to Seagate for warranty repair, and some of them have been sent for the third time. Any suggestions and observations? Thanks! Q. Liu U of Kansas