Xref: utzoo comp.sys.att:6558 comp.sys.ibm.pc:29426 Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!att!mtuxo!mtgzz!drutx!druwy!jaf From: jaf@druwy.ATT.COM (John A. Frieman) Newsgroups: comp.sys.att,comp.sys.ibm.pc Subject: Re: AT&T 6300+ add-in disk problem! Summary: An interleave of 3:1 is standard. Message-ID: <4073@druwy.ATT.COM> Date: 26 May 89 16:05:09 GMT References: <1537@cunixc.cc.columbia.edu> <982@cbnewsc.ATT.COM> <697@soleil.UUCP> Organization: AT&T, Denver, CO Lines: 26 > I have found that I can only go as low as a 5:1 interleave with my 6300. > That's horrible! I only get about 85KB/sec xfer rate which is pathetic. > I'm using a WD XT-GEN controller, but the default DTC controller was no > better. I guess the I/O on a 6300 is WORSE than an IBM XT... > > I used the SPINTEST demo program available on SIMTEL-20 and the HDTEST program > to determine the above. You might try the same. > > Rich Gopstein I have a 6300+ at home and another here at the Lab, both run with an interleave of 3:1. Both have WD controllers and 20 Meg. drives (1 ST-225 and 1 Olivetti both rated at 65 MS seek times). It's been a while since I ran any disk benchmarks but a transfer rate in the 300-400 kb/sec seems about right. The 6300+ has a DMA accelerator for hard disk access. The design for this is published by INTEL with the DMA chip spec., but I haven't seen it used by anyone else. Once you sort out the interleave you might find a copy of QFRESH on a local BBS. This little (15 bytes) gem reduces the number of DRAM refreshs to a workable level. My system picked up 8% on a memory intensive program with QFRESH in the autoexec.bat. Enjoy, John A. Frieman, AGS Info Srv, @AT&T Bell Labs, Denver #include