Path: utzoo!utgpu!water!watmath!clyde!rutgers!bellcore!faline!ulysses!allegra!alice!wilber From: wilber@alice.UUCP Newsgroups: comp.sys.att Subject: Re: More HD on my 3b1. How? Summary: Swapping disks on the 3B1 Message-ID: <7637@alice.UUCP> Date: 19 Jan 88 19:51:56 GMT Organization: AT&T Bell Laboratories, Murray Hill NJ Lines: 40 Posted: Tue Jan 19 14:51:56 1988 Burt Janz writes > In article <7010002@hpcupt1.HP.COM>, gberg@hpcupt1.HP.COM (Greg Berg) writes: > > According to AT&T online support, the power supply installed in > > the 7300 with 20MB is not sufficient to feed 40MB or 80MB disks. > > > > Has anyone done a straight swap of the hard disk with success? > > If so, was the new disk a "fast" or slow variant? > > I guess this means that I've broken the rules of physics again. I purchased > a vanilla 3b1 with 1mb and a 20mb Miniscribe (slow access stepper). As you > may have noticed, that ain't enough to hold all of the development kit and > still have space left for source! I waited until the warranty period > was over, ripped out (carefully but forcefully) the Miniscribe, and shoved > in (gently but firmly) a Seagate ST251. I formatted it using the boot disk > and loaded all the software on it. I've been running happily since. > > The power supply puts out a standard amount of jolts at a specified current > rating. If you can get a drive which rates the same (like I did) but stores > more data... go 4 it! I only have a 3b1 but I understand that there are a few important differences between the 3b1 and the 7300. One of them is that on the 3b1 the power to the disk is taken directly from the power supply, whereas on the 7300 the power to the disk is routed through the motherboard (or so I have heard). So just because it's safe to put a big disk on the 3b1 doesn't mean it's necessarily safe to do so on the 7300. Now I have a question of my own for some hardware mage. How much power does the standard issue 67 Mb (formatted) disk in the 3b1 use? I'm toying with the idea of someday doing that much discussed, apparently little tried, hardware mod that would let me break the 67 Mb limit and go to a bigger disk. (I like to keep source code around.) But I don't want to do this unless I know that the replacement disk doesn't use any more power than the current one. Bob Wilber wilber@research.att.com ihnp4!gauss!wilber Disclaimer: These are the official opinions of the Unites States Government.