gopstein@soleil.UUCP (Rich Gopstein) (04/02/89)
I am in the process of installing a st251-1 in my ATT 6300. To determine the optimum interleave, I formatted the disk several times with INCREASING interleaves, and kept running spintest until the number of revolution necessary to read a track dropped off dramatically (from > 20, down to 5). The interleave turned out to be 5:1 with my WDXT-GEN controller. When I ran the HDTST125 tool, it told be that my current interleave was 6:1 (incorrect), but the optimal interleave was 5:1 (correct). I ran it at several different interleaves, and it was consistently off by one in reporting what the actual interleave was set to. The disk performance check, however, reported track read times that were consistent with the actual interleave. The HDTST125 package reported that the (average?) seek time on the drive was about 40ms. This does not sound right... Has anyone else run it on their 251-1? I would expect something closer to 28ms, since it reported about 60ms access times for my st225 (which is close to what seagate claims). I am also interested in getting better than 5:1 interleaves on my system. Does anyone know of an XT-type controller that supports the 251-1 and might provide for a better interleave? Scott Mueller in his "Upgrading and Repairing PCs" (an excellant book BTW), recommends the OMTI 5520 controller which will run in a stock XT at 2:1, and 1:1 in fast XT clones. Unfortunately, SMS (who made the OMTI) just went out of business... Rich Gopstein ..!rutgers!soleil!gopstein -- Rich Gopstein ..!rutgers!soleil!gopstein
stoppani@hpcupt1.HP.COM (Peter Stoppani) (04/04/89)
>I am in the process of installing a st251-1 in my ATT 6300. To determine >the optimum interleave, I formatted the disk several times with INCREASING >interleaves, and kept running spintest until the number of revolution >necessary to read a track dropped off dramatically (from > 20, down to 5). >The interleave turned out to be 5:1 with my WDXT-GEN controller. > > >When I ran the HDTST125 tool, it told be that my current interleave was >6:1 (incorrect), but the optimal interleave was 5:1 (correct). I ran it >at several different interleaves, and it was consistently off by one in >reporting what the actual interleave was set to. The disk performance >check, however, reported track read times that were consistent with the >actual interleave. > >The HDTST125 package reported that the (average?) seek time on the drive was >about 40ms. This does not sound right... Has anyone else run it on their >251-1? I would expect something closer to 28ms, since it reported about >60ms access times for my st225 (which is close to what seagate claims). > >I am also interested in getting better than 5:1 interleaves on my system. >Does anyone know of an XT-type controller that supports the 251-1 and >might provide for a better interleave? Scott Mueller in his "Upgrading >and Repairing PCs" (an excellant book BTW), recommends the OMTI 5520 controller >which will run in a stock XT at 2:1, and 1:1 in fast XT clones. Unfortunately, >SMS (who made the OMTI) just went out of business... > >Rich Gopstein >..!rutgers!soleil!gopstein >-- I have also had trouble with HDTST125 on my st251-1. However, in my case the program reported the wrong interleave only on the first try. Each time after that the 'interleave report' it got it right! Other programs got the interleave right all the time. My guess is that HDTST125 has a problem. Everex makes a nice AT controller which runs the st251-1 at 1:1 interleave so you might contact them to see if they make a similar controller for the XT. Pete...