doc@holin.ATT.COM (David Mundhenk) (09/01/89)
I have installed a respectibly large number of drives in XT, AT, and 80386 class machines, sometimes with problems and sometimes without a hitch. This is the first time I've tried to install an ST-225 in an AT (I'm almost embarrassed to admit putting something that slow in an AT...8-) and there seems to be a problem. The drive is 'brand new' and I have no reason to suspect that it is defective. No flames on putting this snail in an AT - I'm selling my AT and the guy who's buying it doesn't _want_ anything bigger. Anyway, I'm using a known good motherboard, controller, power supply, etc. and when I boot up I don't even get any kind of error message (the first time I did have to set the drive type in CMOS...). Anyway, I try to run Disk Manager and it says either "hard disk controller malfunction" and doesn't even start, or starts up and says "unable to reset hard disk subsystem" or a reasonable facsimile thereof. I've pulled the drive and plugged in a CDC 94155-86, and it comes up and formats just fine. The controller is a DTC 16 bit (rather old) and I don't know what address the BIOS formatter is at (can anyone tell me? - I've tried C800:5...) so my best other option was Disk Manager. I was told that the ST-225 may need a terminating resistor pack of some kind when used in an AT - is this true? I looked at the drive and don't see any place for something like this, unless it goes onto the berg strip where the drive select jumper is.... Is it possible that this drive is just _TOO_SLOW_ for this machine? It's only a 10MHz. one wait state motherboard... Any suggestions here? Thanks, Dave Mundhenk -- :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: EMAIL: ...!att!holin!doc | "I can't complain but | /^, VOICE: (201)-580-4943 | sometimes I still do"| / } _, , , __ #include <std.disclaimer> | - Joe Walsh | /_./ (_l |/ <~_
JLI@kuhub.cc.ukans.edu (09/02/89)
You don't need any modifications to install an ST-225 in an AT. The drive type should be type 2 (615 cyl. 4 hd.) in most cases unless you have a really uncommon AT mother board. The DTC controllers usually don't have build-in formatter, so you have to use software (such as the Disk Manager) to perform low-level format (some BIOS on the AT mother board has hard disk formatter, such as the DTK-1230C etc.). We have installed ST-225s with DTC controllers (both 2:1 and 1:1 versions, a little odd? But we have to use what we have got.) in different kind of ATs. We have not detected any incompatibility problem so far. You might need to check if the drive selection jumper on the drive is set right. New ST-225 may be defective, especially when you buy in large quantity. We usually buy ST-225 in large quantity, and have bad ones from time to time.