erict@flatline.UUCP (eric townsend) (01/11/88)
I'm running a 3.5Mb, 67Meg 3b1, Unix 3.0, and I want to put at least one more hard drive on it. I think it is *theorhetically* possible, we did it with a Motorola S8000 w/ no problems. Just stuck it on the open card, and did a mount. Well, there was more to it than that, but... Specifically: 1. Has anybody out there tried this? An AT&T Service d00d told me "Well, I've seen people do some strange things to these machines" but wouldn't elaborate... 2. If the drive's SCSI, which I think it is, how can I get unix to recognize more than the 65 megs that it does? I have a 72Mb Hitachi in this one, that's 7 more megs than I'm 'allowed'. 3. If I do crank this up to two or more HD's, at what price? Will the rest of my system grind to a halt while waiting on daisy chained hard drives? Note that I'm not a hardware genius, and would prefer a "Buy part X, unhook your drive, hook up part X, your drive, and the new drive and reboot" answer...:-) -- J. Eric Townsend ->uunet!nuchat!flatline!erict smail:511Parker#2,Hstn,Tx,77007 Just another journalist with too much computing power.| 'Hey, watch me ollie 'Girls play with toys. Real women skate.' --Powell Peralta ad.| this <whump>'
andys@shlepper.ATT.COM (a.b.sherman) (01/13/88)
In article <287@flatline.UUCP>, erict@flatline.UUCP (eric townsend) writes: | I'm running a 3.5Mb, 67Meg 3b1, Unix 3.0, and I want to put at least | one more hard drive on it. I think it is *theorhetically* possible, | we did it with a Motorola S8000 w/ no problems. Just stuck it on the | open card, and did a mount. Well, there was more to it than that, but... | It is theoretically impossible. The disk controller is ST-506, and there is only a data bus connector for one drive. Period. (I looked). | Specifically: | | 2. If the drive's SCSI, which I think it is, how can I get unix to | recognize more than the 65 megs that it does? I have a 72Mb | Hitachi in this one, that's 7 more megs than I'm 'allowed'. | The drive is not SCSI, it's ST-506. The machine has a hardware limit of 8 heads and 1024 cylinders. Someone else has posted a hardware/firmware upgrade to increase this. (Send email to cmv@looney for more information.) | 3. If I do crank this up to two or more HD's, at what price? Will | the rest of my system grind to a halt while waiting on daisy | chained hard drives? | | Note that I'm not a hardware genius, and would prefer a "Buy part X, | unhook your drive, hook up part X, your drive, and the new drive and reboot" | answer...:-) Your best bet is to put the largest drive possible on the system. That is 80Meg (67Meg formatted) unless you do the hardware change. You can't do anything else, because the hardware won't support it. The /dev entries for a second drive are there for the Convergent miniframes used to develop software for the beast. -- Andy Sherman / AT&T Bell Laboratories (Medical Diagnostic Systems) 480 Red Hill Road / Middletown NJ 07748 / (201) 615-5708 UUCP: {ihnp4,allegra,akgua,cbosgd,mtune....}!shlepper!andys INTERNET: andys@shlepper.ATT.COM
wtm@neoucom.UUCP (Bill Mayhew) (01/13/88)
Ver 3.51, though not terribly publicized will let you custom enter parameters grater than 67 meg,... but the harware won't let you do it in reality becuase the dang HD controller chip ain't got enuf brainz to recognize more than 67 megs. There is a rumor that Convergent Technologies has a patch for their incarnation of the "Safari" PC to enable bigger drives. The mod requires adding about 6 jumper wires on the motherboard, adding a PAL decoder chip and swapping in a different HD controller. In theory, that should cost under $50 if you do the mod yourself. I haven't tried doing this [yet] because I have a feeling that my warranty isn't going to be worth shoot if I kludge the motherboard. The 3b1/7300 has just a plain old ST506/412 disk interface (unless they're doning something sneaky). To answer the question, I don't think a 2nd drives is a practical reality. Kludging for one bigger drive is do-able.
gberg@hpcupt1.HP.COM (Greg Berg) (01/14/88)
% / hpcupt1:comp.sys.att / andys@shlepper.ATT.COM (a.b.sherman) writes % Your best bet is to put the largest drive possible on the system. That % is 80Meg (67Meg formatted) unless you do the hardware change. You can't % do anything else, because the hardware won't support it. The /dev % entries for a second drive are there for the Convergent miniframes used % to develop software for the beast. % ---------- 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?
hartman@uiucdcsm.cs.uiuc.edu (01/15/88)
/* Written 11:46 am Jan 13, 1988 by gberg@hpcupt1.HP.COM in uiucdcsm:comp.sys.att */ > According to AT&T online support, the power supply installed in > the 7300 with 20MB is not sufficient to feed 40MB or 80MB disks. According to a posting from Craig Votava (ihnp4!looney!cmv) a while back, the power supply is the same in the 7300 and the 3b1, only the way the power is routed to the drive is different. > Has anyone done a straight swap of the hard disk with success? > If so, was the new disk a "fast" or slow variant? I just (last week) installed a 40mb drive to replace the 20mb drive in my 7300. My original drive was a Miniscribe 3425, which has an average access time of 53ms. I replaced it with a Seagate ST251, a 40ms drive. The swap is fairly easy, once you figure out how the thing comes apart. Response time is a little faster (windows definately seem snappier!), and I have not had any problems yet (knock on wood...). --------------------------------------------------- Mark Hartman ihnp4!uiucdcs!hartman hartman@m.cs.uiuc.edu
bhj@bhjat.UUCP (Burt Janz) (01/17/88)
In article <7010002@hpcupt1.HP.COM>, gberg@hpcupt1.HP.COM (Greg Berg) writes: > % / hpcupt1:comp.sys.att / andys@shlepper.ATT.COM (a.b.sherman) writes > % Your best bet is to put the largest drive possible on the system. That > % is 80Meg (67Meg formatted) unless you do the hardware change. You can't > % do anything else, because the hardware won't support it. The /dev > % entries for a second drive are there for the Convergent miniframes used > % to develop software for the beast. > % ---------- > > 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! Burt Janz ..decvax!bhjat!bhj (my Microport system) ..decvax!bhjatt!bhj (my 3b1)
wilber@alice.UUCP (01/19/88)
Burt Janz <bhj@bhjat.UUCP> 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.
wilber@alice.UUCP (01/21/88)
I wrote: > 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. Well I was right about how power is routed in the 7300 but was apparently over cautious -- Craig Votava just posted a long article in unix-pc.general and att.sys.unixpc about upgrading his 7300, and among other things he put in a moby (86 Mb) disk. So it seems to be an okay thing to do. Bob Wilber wilber@research.att.com ihnp4!gauss!wilber Disclaimer: These are the official opinions of the United States Government. Emacs -- it's not just a text editor -- it's a cult.
bhj@bhjat.UUCP (Burt Janz) (01/22/88)
In article <7637@alice.UUCP>, wilber@alice.UUCP writes: > 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 Now I'm confused. The monitor says "ATT UNIX PC", the box says "3B1", and support says that I have a 3B1. But, the power supply IS routed on the motherboard. I found this out when my system went dead. I shut my system down over the Christmas holiday weekend to prevent any possible problems from power outages. So, I came in on Monday and turned the system on. Noise, dots on the screen... and more dots... and more dots... The hard disk never went through it's initialization. I took the system home, opened it up, and used my DVM to check the power supply. There are two sets of power cables on the motherboard: one for the hard disk, and one for the floppy. The floppy showed both 5v and 12v, but the hard disk showed only the 12v. Using the DVM, I discovered that the board runs from the power supply went to both the cable sets... parallel connection. So, I resoldered the wires to the motherboard, and... POWER!!! A bad solder connection. Please note that I said that the power runs were on the motherboard. My system is (supposedly) a 3B1. So, do I have a 7300 in a 3B1 wrapper? Burt Janz ..decvax!bhjat!bhj ..decvax!bhjatt!bhj
wtm@neoucom.UUCP (Bill Mayhew) (01/25/88)
My 3B1 hard disk has a cable that runs straight to a connector on the power pack module. My first motherboard was that way. When my machine boots, it says something like "Main Board P3..P5" just after the kernel loads. There was a sticker on the first motherboard I had that said "Rev E", I think. When I got a strnage panic message, AT&T decided to replace the motherboard a few weeks ago. The replacement board had obviously been in used some place else, as there were marks of previous lock washers around the screws, etc. That board had a sticker that said "Rev H", I think. Physically, both boards looked identical and had the very same fix-up jumper wires. Anyway, both motherboards had only a single power socket for the floppy drive, though there were some solder pads where a power cable for the hard disk could have been put. Most of the ICs on my "new" motherbaord were date-coded about the middle of 1986. I don't know how feasible it might be to solder your drive power cable right to the power pack. I agree that it would be a good idea to "cut out the middle man" and not send hard disk power through the motherboard. --Bill