neese@cpe.UUCP (09/29/88)
> Has anyone put together any IBM-AT-compatible configuration that >permits the dumping of 44-megabytes/minute of data to a hard disk? I've >been told that there are high-speed buses available for special-purpose >applications, but I've not been able to find them. Also, can anyone >recommend fast hard disks for this purpose? Well, that is about .73Mbyte/sec. (730KB/sec). One of the things you didn't mention; Are you dumping data in large chunks (>16K) or one sector at a time. If you are doing large chunks, then you can easily get that type of performance with the Adaptec SCSI Adapter (AHA-1540, Tandy 25-4161), and a resonable SCSI Hard Drive. You didn't mention the size of the hard drive either. If high speed writing is your goal, then I would recommend the CDC Wren IV/V drives. If your need super fast data acquisition, then I recommend the Quantum P40/80 drives. The CDC drives, when writing large chunks, could easily achieve 50MBytes/minute with this combination of Adapter/Drive. The Quantum drives could easily provide throughput in excess of 60MBytes/second while reading. Of course, on the other hand, if you use a Future Domain TMC-830 and a Conner 40MB drive, then you might be able to get to 22MByte/second. If you stand on one foot and hold your breath. Roy Neese Tandy Computer Product Engineering UUCP@ killer!ninja!cpe!neese
hoctor@osiris.cso.uiuc.edu (09/29/88)
I am using an Adaptec ABC-237x controller with a Miniscribe 3675. The controller is RLL and permits 1:1 interleavine of the drive which allows about 800K/sec throughput. This is approximately the throughput that your are looking for and it operates in a standard AT bus. We payed about $675 for the combination through a local dealer. Note that the Miniscribe 3675 is a 70ms access time drive, but throughput is the real test. If you are using something disk intensive, you might look for something with a better access time.
thaler@speedy.cs.wisc.edu (Maurice Thaler) (09/30/88)
I am a confused person. I have a Dell SYSTEM 310 20Mhz 386 and a Seagate 4096 80Megabyte 28ms drive. I just bought an Adaptec ACB-2372 controller and installed it and am getting less than spectacular results. It is better than the original results with the Western Digital controller but not up to the claims of Adaptec. With the WD controller I was getting about 250K/sec data transfer. With the Adaptec I am getting about 450K/sec. This is much lower than the 700-750K advertised. I have trouble believing that my bus is the culprit, but it could be. I had a very long drawn out struggle trying to get the Perstor 16-bit controller to work and never was able to get it to work. The latest version of the ROM that they sent me formatted the 4096 fine, but the darn thing would not boot properly. It would try to do a recalibration and then just report that it was a non-bootable disk. I had many VERY long converstations with Perstor and they ended up saying that they could get it to work if I sent them my machine.... something I was not willing to do. Several friends of mine have been trying this Adaptec card, which was priced very reasonably, so I tried it. The problem is the data transfer rate. I have stripped out several things from my CONFIG.SYS and that helped some but still not enough. QEMM.SYS 4.1 from Quarterdeck slows things down by at least 100K/sec when I map RAM so I can use the LOADHI program to move TSR's to High Memory. When I install EMCACHE, it slows things down even worse. When I boot from a CLEAN floppy with DOS3.3 I get my best rate at about 550K/sec but that is still much lower than 750 or 700. My questions are: Is this the wrong hard disk for this card? If not, any suggestions for speeding things up? What is the right, affordable hard disk that does work with this card in the 70-80Megabyte range (before RLL'ing)? I need a lot of space because I use my setup for doing desktop publishing and just the fonts take up about 20Meg or so. I need a lot of speed on the I/O which is why I am into the high data transfer rate.