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Xacalite
October 9th, 2017, 01:37 AM
The original 5160 had a 10 MB HDD.
Later 5160 variants had 20 MB.
PS/2 Model 30 (8086) had 20 MB.
All the clones I saw had 20 MB, with the exception of some low-end ones with no HDD at all - eg. Amstrad PC1512SD, Commodore PC-10, and many portables.

But I've never seen an XT-class machine with an HDD greater than 20 MB.
Back in the era, of course - I'm not talking about all the XTs we play with nowadays.

So, what are your experiences? Did you ever encounter an XT with >20MB? How common such machines were?

jimmaxx
October 9th, 2017, 04:11 AM
I have a tandy sx with 425mb

KenEG
October 9th, 2017, 04:33 AM
My Commodore Colt had a 20 MB drive. I thought it was huge and so I could never fill it up. Imagine my surprize about 6 months later when I tried to install something and was informed that there wasn't enough room.

keenerb
October 9th, 2017, 05:08 AM
The original 5160 had a 10 MB HDD.
Later 5160 variants had 20 MB.
PS/2 Model 30 (8086) had 20 MB.
All the clones I saw had 20 MB, with the exception of some low-end ones with no HDD at all - eg. Amstrad PC1512SD, Commodore PC-10, and many portables.

But I've never seen an XT-class machine with an HDD greater than 20 MB.
Back in the era, of course - I'm not talking about all the XTs we play with nowadays.

So, what are your experiences? Did you ever encounter an XT with >20MB? How common such machines were?

A 40mb drive was an option for Tandy 1000 computers. I have a non-functional one myself, but I've seen far more 20mb Tandy drives than 40mb.

SomeGuy
October 9th, 2017, 05:15 AM
For some time in the late 80s 20MB drives, usually the Seagate ST-225, were the best price point for a budget system. Look in a catalog and you might see options of 20, 32, 40, 64, and 80mb drives. A low-end budget system would often be a Taiwanese turbo XT motherboard, monographics video card and monitor, and 20mb hard drive. If you had more money to spend you would go with a mid range 286-AT and ~40MB hard drive. If you had lots of money you might go with a new fangled high-end 386 and as much HD space as you could throw at it. Finally, if you had more money than brains, you would get a Macintosh. :P

glitch
October 9th, 2017, 05:39 AM
HardCards were a popular option, I think my second Leading Edge Model D (an XT class machine) came with a 40 MB XTA (8-bit IDE) HardCard workalike (not an actual, official Plus HardCard). SCSI existed for 8-bit ISA back in the day, one of the more common cards, the Future Domain 850, was available from IBM with a PS/2 Model 25/30 specific ROM, so presumably people were using SCSI hard disks with 8-bit ISA PS/2s.

My personal XT, the first computer that was actually mine and not a family computer, has a 70 MB Seagate Wren II MFM drive in it. The drive wasn't original to the machine, but is from the right era that you might have found such a configuration in the wild at the time (or not, it was a very expensive drive when it was new). I plugged it in there because it was a hard drive and I had an 8-bit controller for it, not due to originality or anything. I remember it taking a very long time to low-level format!

SpidersWeb
October 9th, 2017, 06:24 PM
A 40mb drive was an option for Tandy 1000 computers. I have a non-functional one myself, but I've seen far more 20mb Tandy drives than 40mb.

My Tandy 1000 came with the "40MB Smart Drive" option pack. It's the only Tandy 1000 I have, so that's "100%" for me!



Have also had clones turn up with 30MB RLL drives, but really that's just a 20MB drive with lipstick, and I've pulled a FH 130MB drive out of a 5150 (original 63W supply too).
But I'd say more than 20MB on an XT was kind of a special case.

Even 286/386 machines 20 to 40MB seems to be the average consumer area.

Chuck(G)
October 9th, 2017, 07:15 PM
I ran a generic Turbo-XT motherboard with a Priam 514 drive (~100MB). I modified my own BIOS. Lotsa partitions.

kgober
October 10th, 2017, 06:12 AM
Keep in mind that DOS 3.x limited hard disk volumes to 32MB, so if your computer had a larger disk it had to be partitioned into smaller chunks (for example a 40MB drive might be split into a 32MB C: drive and an 8MB D: drive, or it might be split equally into 20MB C: and D: drives). An experienced user could deal with this, but for people new to DOS (or new to computers) it was simpler to just have a single C: drive.

One disadvantage of getting a computer with a 40MB drive was that if you were unhappy with how the drive had been partitioned for you, you would need to repartition it and reinstall everything yourself. When 60MB and larger drives became more affordable the partitioning scheme had pretty well standardized to "as many 32MB partitions as you can fit, and whatever is left in the last partition".

David_M
October 10th, 2017, 06:26 AM
My XT came with an Seagate ST-225 but it wasn't long before I replaced the controller with an RLL controller and ran the drive as a 30M drive.
My first AT clone I used a 1:1 interleave RLL controller with a 70M Priam drive which gave me 105M, soon after I filled that and went with a 300M Toshiba scsi drive.

Chuck(G)
October 10th, 2017, 08:32 AM
Partitioning didn't exist for very early DOS, so some controllers allowed you to take your 32MB hard drive and make it appear as two 16MB drives.

A similar thing was done with Apple II early hard drives--make a hard disk look like a pile of floppies.

Xacalite
October 10th, 2017, 08:51 AM
A similar thing was done with Apple II early hard drives--make a hard disk look like a pile of floppies.
Wasn't something like this available for IBM PC as well? I mean there was some external HDD for 5150 in the DOS 1.xx era.

JoJo_ReloadeD
October 10th, 2017, 08:52 AM
I have several Amstrad 2086s, those are 8086s XT class machines with a 30mb RLL hard disk.

Chuck(G)
October 10th, 2017, 12:02 PM
Wasn't something like this available for IBM PC as well? I mean there was some external HDD for 5150 in the DOS 1.xx era.

Perhaps, but by 1.26, there was a limited amount (FAT12) of hard disk support available. No subdirectories, through.

bear
October 10th, 2017, 12:45 PM
The Taiwanese turbo XT clone my family bought toward the end of the '80s had a 40 MB Miniscribe in it. So certainly it wasn't unheard of. But I do recall many of the ads I spent all kinds of time memorizing were mostly for 20 or 30 MB systems, even for a while after. The Leading Edge Model D2 (10 MHz 80286) we upgraded to around 1990 had only a 30 MB drive (which we replaced with the 40 MB drive from the XT clone). My vague recollection is 1989 or 1990 was around the time I started regularly seeing 40 MB drives as a base option.

mR_Slug
October 10th, 2017, 07:59 PM
Wasn't something like this available for IBM PC as well? I mean there was some external HDD for 5150 in the DOS 1.xx era.

This item may have operated like this as it was for multiple different platforms. I'm sure I read somewhere of a Winchester for the PC that worked like a stack of floppies. I guess it would have been good for compatibility.
https://books.google.com/books?id=w_OhaFDePS4C&pg=RA1-PA52&lpg=RA1-PA52&dq=Santa+Clara+Systems+SCS-5&source=bl&ots=cXoCjnzQfh&sig=PtulRpI_eLPa5uLnwxpGO10Q4wM&hl=en&sa=X&redir_esc=y#v=onepage&q=Santa%20Clara%20Systems%20SCS-5&f=false

Denniske1976
October 12th, 2017, 04:40 AM
My 1988 (or maybe 1989) Vendex HeadStart LX came with a 40MB MiniScribe factory installed too, controller is mainboard integrated (makes it rather specific for using a 8450XT, tried a Seagate ST-3040A/X to no avail since it only sees 20MB with that disk).

But I was the first in my class with 40MB disk in their XT and 3.5" HD floppy drive (and 4-color CGA for that matter) LOL :-D

1ST1
October 13th, 2017, 02:08 AM
ATARI PC 3 (8088 CPU) has 30 MB St506 RLL hardisk.

Stone
October 13th, 2017, 03:01 AM
ATARI PC 3 (8088 CPU) has 30 MB St506 RLL hardisk.The ST-506 is a 5 MB MFM drive.

Xacalite
October 13th, 2017, 07:34 AM
The ST-506 is a 5 MB MFM drive.
Yes, but the term "ST-506" (or "ST-412") is also used for the interface introduced with these drives.

Trixter
October 13th, 2017, 11:00 AM
My XT came with an Seagate ST-225 but it wasn't long before I replaced the controller with an RLL controller and ran the drive as a 30M drive.

Do you recall encountering any issues doing that? Higher occurrence of bad sectors, etc.?

Stone
October 13th, 2017, 11:18 AM
Do you recall encountering any issues doing that? Higher occurrence of bad sectors, etc.?I've run several MFM drives with RLL controllers with no issues whatsoever. They were Seagate ST-225, Maxtor XT-1140, and Maxtor XT-2190.

Casey
October 13th, 2017, 03:41 PM
In the late 80s I bought a clone turbo XT. Had an EGA card & monitor (the latter a Samsung), and I dropped in an ST-238R with an Adaptec 2070a controller, which was pretty much designed for the 238. Worked quite nicely.

Stone
October 13th, 2017, 04:01 PM
IIRC, the ST-238R is the same piece of hardware as the ST-238 -- only the label is different.

krebizfan
October 13th, 2017, 04:25 PM
As far as I can tell, there never was a MFM ST-238 drive. The ST-238R is an RLL equipped ST-225; I think ST-138R was the same drive. All of these have 2 platters. Just to be tricky, Seagate also had an MFM ST-138 which had 3 platters.

Casey
October 14th, 2017, 04:51 PM
Can't speak for the 138, but back in the day I heard more than once that a 238 was a 225 with better electronics. Also knew several folks who used David's trick of formatting a 225 with an RLL controller. Seemed risky to me at the time.

These days, now that I have a 2070a controller again, I am sooo tempted to pick up a Mitsubishi MR-535 MFM if another turns up, just to see I can make it work reliably as RLL.