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Old 15th December 2016, 3:00 PM   #46
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Originally Posted by shane41 View Post
I'd be worried about theft / loss / damage / catastrophic events / flood & fire.
Some of the guys here know effort I've put in collecting.

You can only do it once. They are too expensive to buy these parts again.
So yes as a History of Computers idea hang onto them & run /cycle these machine. That museum will be possible one day.

462 for life........show me
Yeah I am vaguely worried about theft/disaster but try explaining how old computers/video games can be considered "collectables" to the insurance mob... the last time I asked they wanted a professional valuation... valuers had no idea what I was going on about

I'll get to 462 in good time. I have a vague idea where that rig is, although I think I sold my top end one (Gigabyte board with 4x DDR400 dual channel, Athlon 3200+). Think the one I have left is the 2400+...

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Originally Posted by Flamin Joe View Post
There's no hard and fast rule as to what size HDD's (or RAM for that matter) were used since a lot of these CPU's were still being produced in systems for a good 10 years. 8088 - Early 80's to late 80's, 286 - early 80's to early 90's, 386 - Mid 80's to early 90's, 486 - late 80's to mid 90's. So it's not surprising to find early variants of these systems having minimal HDD/RAM capacity or even using older technology, for example RLL/MFM drives in early 386's and IDE in later models.

It's nothing like today where you are pratically changing CPU sockets as often as you change your underwear.
Yeah this is true - it gives me the shits with Intel changing every other week. The worst was towards the end of the 775 era where 775 could still be a serious gaming rig, but 1366 and 1156 were also available, and none of the bloody coolers fit on any other sockets

Still, I'm surprised to hear there was that much variation - I've never seen a RLL/MFM drive in a 386. But it does make sense

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Originally Posted by Groff View Post
My XT back in the mid-late 80's had a hardcard in it.
Slot in ISA card that was 10MB from memory.

Bit like today's PCIe SSD. My how times have changed and yet some things are still similar.
Interesting, from Wikipedia: "their first Hardcard had a 10 megabyte (MB) capacity; its suggested retail price was $1,095"

LOL WAT. I realise everything was a lot more expensive back then but WOW.

And yeah, things go in waves, we started with big servers and dumb terminals / VDUs, then we had powerful desktop PCs at every desk, then there were Wyse terminals and we were back to centralised processing power, and then those sort of faded out in favour of Brix / NUC, but there is still more and more capability for distributed computing power through cloud server services...

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Originally Posted by elvis View Post
If you want to test out DOS games in a browser before you go to the effort of buying/installing them:

https://archive.org/details/softwarelibrary_msdos_games
Thanks for the heads up - could come in handy - but in general I don't mind the effort

Quote:
Originally Posted by Flamin Joe View Post
I've got one of those hardcard's except it's a later model so not XT compatible unfortunately. Hardcard II Plus if I recall correctly, 16 bit ISA and can't be used as a boot drive as it requires a device driver. It was more designed to be an extra hard drive for systems which didn't have space for another drive inside the case.

Pretty nifty, VERY long card and the drive is suprisingly slim (which it has to be) for that era.
Hm, another Hardcard owner in the same thread, that has to be some kind of OCAU record

I might have to hunt one down for one of these rigs but I worry that if I start hunting down every cool bit of random retro tech that takes my fancy, my funds will deplete even more severely

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Buying? Once a pirate, always a pirate.
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Originally Posted by elvis View Post
I'm at a point in my life where I'm trying to undo my past naughtiness.

I quite like buying old games. Right now, the effort in getting old games working is more around licensing than anything else. I hate the idea that some software is lost to time, and if I spend a few bucks on an old game (even if I never play it again, but did in the past), I at least know I'm sending a message to current license holders and publishers that it's worth their time to dig up these old games and make the effort to keep them in circulation.

I've "unpirated" a number of games in the last few years. And again, some I've never played since buying them, but I'm at least a little happier knowing that I've paid for them at some point, even if it wasn't the full retail price back when it was released.
I'm on the fence with this. My current philosophy is that if the content I want is:
a) easily accessible
b) reasonably priced and
c) does not have insane DRM issues
then I'll buy it.

I have also gone back and legitimized a lot of my video game library (EB was selling PS2 stuff for like $5 a game for a few years there so it wasn't exactly an expensive undertaking )

Most current games that I want, I wait a few months and buy on Steam sales so the developers can keep making good titles.

My current gripe is with subscription-based streaming TV and movie services. Tried netflix for a while, but there was no James Bond. And only Mission Impossible 3, no 1 or 2. And no Fast & Furious. I refuse to have to subscribe to multiple services to access the content I want, and I also don't like the idea of paying for the "use" of something (streaming) in general, I would rather pay $2.99 for Mission Impossible 1 as a download than $10 a month for unlimited streaming...

Thing is with the old games, at the time all the stuff I was playing was almost all shareware. So I never had 2nd/3rd episodes of games or extra levels past the shareware inclusions.

To stay true to the era, I think they probably should be the shareware versions back on there, but I also wouldn't mind having the complete versions of all the games

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Originally Posted by elvis View Post
And as I've said before too, just because games are old, doesn't make them bad or unplayable. There's a whole generation of kids now who've never played these, and can find just as much joy playing them for the first time today as we did when we were kids.
+1 to this 100% agree upvote etc

In fact, in my opinion, a lot of the older games are actually better games than the current offerings. Sure, they're dated, but conceptually there was a lot more creativity back then, to some extent they were more challenging and had better replay value, and also (at least from my experience) there were a lot more really good games, and a lot less shovelware and junk released to make an extra few $ (Cull of Dooty 27, anyone? Buttlefield 194222219889?)

And developers were supporting the community and adding cool features like LAN play, and making dedicated server exe's available, rather than restricting LAN play, having stupid DRM blocks and forcing people to use shitty matchmaking bullshit
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Old 23rd December 2016, 7:42 PM   #47
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Is anyone driving from Sydney to Melbourne in the next year?

I have an IBM 8513 CRT to give Sonic, but I have no economical way to get it to him.
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Old 15th March 2017, 11:12 PM   #48
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Where's the updates at?
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Old 21st March 2017, 10:15 AM   #49
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Originally Posted by sammy_b0i View Post
Where's the updates at?
♫ Hold on, they're coming! ♫

(family life with a 7-month-old and 2-and-a-bit-year-old has beenpriority, sorry)


Last edited by Ma Baker; 19th April 2017 at 11:25 PM. Reason: YouTube link fixed
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Old 19th April 2017, 10:38 PM   #50
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Default IBM 5150!

Update done!

http://forums.overclockers.com.au/sh...php?p=17395741

Got the IBM 5150, works great

So for anyone else who knows about these things:

- Any idea why there is no RAM count / POST screen when it boots? I'm sure my original one used to have this. This one just sits with a flashing cursor for 3~4 mins and then runs autoexec.bat

Could it be to do with the screen / graphics adaptor or the MODE command or some such? I'm too young to know of these things

- Can anyone shed any light on the add-in cards?
The first two are simple: one for the FDD, one for the HDD. Done.

Then it gets tricky. There are two more full-length cards in there. The printed quote lists a:

"Taxan KIF 3230 Multifunction board 384K" and a
"Mono display and printer adaptor"

The handwritten receipt lists a:

"Persyst Mono Combo Brd + 384K"

This gives us a total of:
2x female DB9 ports, 2x female DB25 ports, 1x male DB9 port (external)

Going off the labels on the back, one is for the monitor, one is for a printer, and the external one is obviously RS232. That leaves:

- The female DB9 port below the LPT port - what's that for? Can't be CGA/EGA/display, since that's on the other card??

- I wouldn't've thought there would usually be a LPT port and a display port on the same card, but "Mono Combo Brd" suggests that maybe that's what it is?

- What's the 384k? There are a stack of chips on one of the cards, which could be 384k of something, I would think it's unlikely to be 384k of video memory considering the PC has only 256k of actual RAM, but could you just add extra RAM on a slot card like that?!

- The large port on the back of the FDD card - for an external floppy drive??

Further reading: http://www.minuszerodegrees.net/5150...5160_cards.htm

Check this out from the receipt:
IBM PC 256k $3156
20mb Hard Disk $3191 WOW
Persyst Mono Combo Brd + 384k $1249 - what is this even FOR
Taxan KX-1212 Monitor $338
Taxan "Cable"? (can't quite read it) $35
PC DOS $95
Multiplan $325

And now - piccies!

Museum Display Piece - looks nice! Wish I had enough space to have all these rigs set up on the bench all the time



The Guts - interesting to see how much and yet how little the layout of a PC has changed in the last 30 years



Rear IO - plug in baby!



20mb Hard Drive - that's ~$9k worth of storage right there (adjusted for inflation). The price of the hard drive was more than the PC itself. Wow.



Australian Made!



Printed Quote - Myer, selling PCs in Australia since, well, since PCs existed



Receipt - makes my usual trips to MSY look like trips to the $2 shop

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Old 20th April 2017, 1:11 AM   #51
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8400 clams Oh crap. Lucky was friends with the sales person.
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There is a group of us that get incredibly erect over such hardware. Maybe post in the retro section?
Haha ...........might be a bit rude that picture.
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Old 20th April 2017, 8:19 AM   #52
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Pre-GST days too. 20MB would have been huge for that PC ... so price is probably fair. I mean how many 360kb floppies would you need to fill it up? ... 56.8888888889 apparently
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Old 20th April 2017, 9:21 AM   #53
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The 384K on the expansion board would be extra system RAM. The IBM 5150 motherboard came in two major revisions, earlier boards had anywhere between 16K-64K of onboard memory, later revisions (which is what yours would be) had between 64K-256K of onboard memory. It seems like the original owner was a big spender being able to afford the top of the line 256K configuration!

The rest up to 640K would have to be done with expansion cards which came in all sorts of flavours. Some just pure memory, others had memory + I/O ports. Back then expansion slots were premium real estate so it's not uncommon for expansion RAM and display cards etc to be bundled with I/O ports in order to save on slots.

Your system should have a total of 640K (256K + 384K). No idea why there are the two however, I'm guessing one would have the RAM expansion disabled. Seems like an odd and expensive way to get more serial/parallel ports if that's the case but then again if they were willing to shell out for the top of the line configuration then maybe money was no issue.

Quote:
Originally Posted by sonicthemouse View Post
- Any idea why there is no RAM count / POST screen when it boots? I'm sure my original one used to have this. This one just sits with a flashing cursor for 3~4 mins and then runs autoexec.bat
Are you sure your remembering correctly? As far as I'm aware the 5150 never had a POST screen so there is no memory count. It is however present in the 5160.
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Old 27th April 2017, 7:32 PM   #54
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Only now came across this thread ...

I haven't seen mentioned any ref to Australian Computer Museum Society
The site doesn't look like it's very active ATM, but there is a copyright notice at the bottom of the home page that says 2017.
You might be able to dig up some helpful people there.
Or get roped in and become one of them.

Some may find their Computing History Timeline interesting.

My first "PC" was a homebuilt job, ran CP/M-80 in a Zilog Z80 CPU at 4MHz.
S-100 bus chassis, 2 x DS/DD 8" floppies that I usually formatted with 512B sectors, giving 1.2MB per disc.
This was similar gear to that of the Altair 8800 mentioned in the Timeline.
If set up to auto-load a smart line-based text editor, it would boot the O/S and load the editor about 0.25 sec after you closed the door on the continually-spinning floppy.
Try that with anything modern.

First computer I ever saw would have been SILLIAC at Sydney Uni Sch of Physics, but I had no idea of how it worked, being just a high school kid from the bush on a student group tour.
Apart from the machine at the old Museum of Applied Arts & Sciences in Harris St Ultimo (site now UTS) that did nothing other than play 0's and X's, that is.
Hey! They even have some bits of SILLIAC there !

Last edited by BlindFreddie; 27th April 2017 at 7:50 PM.
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Old 28th April 2017, 9:11 AM   #55
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Originally Posted by BlindFreddie View Post
I haven't seen mentioned any ref to Australian Computer Museum Society
The site doesn't look like it's very active ATM, but there is a copyright notice at the bottom of the home page that says 2017.
You might be able to dig up some helpful people there.
Or get roped in and become one of them.
I think I've mentioned it in another thread, but the best resource online for the IBM 5150 let alone any IBM of that era is hands down www.minuszerodegrees.net. The guy who runs that website is extremely knowledgeable and he's "local" too (for those that live in Melbourne). He's often found on the Vintage Computer Forums providing answers and he's helped me quite a few times too. Absolute wealth of information and was one of my inspirations for creating my website.
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Old 28th April 2017, 1:29 PM   #56
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Originally Posted by shane41 View Post
8400 clams Oh crap. Lucky was friends with the sales person.
Yeah. In some ways I kinda wish PCs still cost this much, and people learned a bit about how to use them and treated them with a bit of respect, rather than disposable "toys" (some of the other kids when I was at high school used to go through at least a laptop a year )

Quote:
Originally Posted by TaXy DriVar View Post
Pre-GST days too. 20MB would have been huge for that PC ... so price is probably fair. I mean how many 360kb floppies would you need to fill it up? ... 56.8888888889 apparently
But still, same price for HDD as whole PC!?

Quote:
Originally Posted by Flamin Joe View Post
The 384K on the expansion board would be extra system RAM. The IBM 5150 motherboard came in two major revisions, earlier boards had anywhere between 16K-64K of onboard memory, later revisions (which is what yours would be) had between 64K-256K of onboard memory. It seems like the original owner was a big spender being able to afford the top of the line 256K configuration!

The rest up to 640K would have to be done with expansion cards which came in all sorts of flavours. Some just pure memory, others had memory + I/O ports. Back then expansion slots were premium real estate so it's not uncommon for expansion RAM and display cards etc to be bundled with I/O ports in order to save on slots.

Your system should have a total of 640K (256K + 384K). No idea why there are the two however, I'm guessing one would have the RAM expansion disabled. Seems like an odd and expensive way to get more serial/parallel ports if that's the case but then again if they were willing to shell out for the top of the line configuration then maybe money was no issue.
Yeah I'm going to have a closer look at the add-in cards on the weekend and see what I can learn. From looking on that www.minuszerodegrees.net (which as you mentioned is an absolutely excellent reference), it looks like perhaps the system shipped with a standard I/O card which just had a monitor port and a parallel port, and they added in a "monster" IO card with extra RAM, it's own monitor and parallel ports and a serial port.

My guess at this stage is that the card it shipped with is basically redundant, but the board is configured to use that card as the display card.

Is there an easy way to check how much RAM you have installed in DOS 2.1

Usually himem or emm386 or some such would give you a summary but I don't think this has either of those...?

Edit: Also, would the add-in RAM be slower than the on-board RAM? Obviously these days the speed of the bus between the CPU and RAM is orders of magnitude faster than the "slot card" bus but perhaps going back through time this was not always the case?

Quote:
Originally Posted by Flamin Joe View Post
Are you sure your remembering correctly? As far as I'm aware the 5150 never had a POST screen so there is no memory count. It is however present in the 5160.
I'm remembering the RAM count correctly, because I was surprised when this one didn't have one. But it's quite likely that I had the 5160 back then and not the 5150 and that's the bit I'm remembering wrong

Quote:
Originally Posted by BlindFreddie View Post
Only now came across this thread ...

I haven't seen mentioned any ref to Australian Computer Museum Society
The site doesn't look like it's very active ATM, but there is a copyright notice at the bottom of the home page that says 2017.
You might be able to dig up some helpful people there.
Or get roped in and become one of them.

Some may find their Computing History Timeline interesting.

My first "PC" was a homebuilt job, ran CP/M-80 in a Zilog Z80 CPU at 4MHz.
S-100 bus chassis, 2 x DS/DD 8" floppies that I usually formatted with 512B sectors, giving 1.2MB per disc.
This was similar gear to that of the Altair 8800 mentioned in the Timeline.
If set up to auto-load a smart line-based text editor, it would boot the O/S and load the editor about 0.25 sec after you closed the door on the continually-spinning floppy.
Try that with anything modern.
Thanks for the links - will investigates and see where I get to.

Your first "PC" sounds awesome - born in '88 I have actually never seen a real-life 8" floppy nor used a continually-spinning floppy drive.

When you say home-built, was it sold as like a kit thing, or you actually worked out what parts you'd need to make it go and ordered everything individually and assembled? Either way, I am impressed!

And yeah the world seems to go backwards:
- boot time to Windows 3.1 desktop "ready to use" on my 386 is significantly faster than to Win 10 desktop on my 5930K (and fundamentally, is it any different, has anything really improved? I'm considering moving back to Windows 3.1 as my main OS and seeing how long I can last / work around things like YouTube plug-ins... pretty sure Win 3.1 (well 3.11 for networking support) won't be able to run the latest Firefox
- mobile phone battery life is worse than it was ~7 years ago
- it took me a few minutes to use a EFTPOS machine the other day because to choose between CHQ/SAV/CR you had to use up/down soft keys and enter on the 3" colour touchscreen.... if you have a touchscreen, you should be able to just touch the option you want, and besides that it was easier and quicker when there was a button for each one. The world is run by morons.


Quote:
Originally Posted by BlindFreddie View Post
First computer I ever saw would have been SILLIAC at Sydney Uni Sch of Physics, but I had no idea of how it worked, being just a high school kid from the bush on a student group tour.
Apart from the machine at the old Museum of Applied Arts & Sciences in Harris St Ultimo (site now UTS) that did nothing other than play 0's and X's, that is.
Hey! They even have some bits of SILLIAC there !
Should collect all the bits and rebuild it

Quote:
Originally Posted by Flamin Joe View Post
I think I've mentioned it in another thread, but the best resource online for the IBM 5150 let alone any IBM of that era is hands down www.minuszerodegrees.net. The guy who runs that website is extremely knowledgeable and he's "local" too (for those that live in Melbourne). He's often found on the Vintage Computer Forums providing answers and he's helped me quite a few times too. Absolute wealth of information and was one of my inspirations for creating my website.
Yeah I've done a bit of reading on minuszerodegrees but yet to get in touch with the author or head over to vcfed. I'll get to it at some point

In the meantime I'll hopefully fire up the next PC for this thread over the weekend, stay tuned!

Last edited by sonicthemouse; 28th April 2017 at 1:35 PM.
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Old 29th April 2017, 5:03 PM   #57
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Originally Posted by sonicthemouse View Post
Is there an easy way to check how much RAM you have installed in DOS 2.1

Usually himem or emm386 or some such would give you a summary but I don't think this has either of those...?
Welcome to the world of early DOS days. Isn't it fun? No way to check RAM amount in early versions, even the "mem" command wasn't a feature until MS-DOS 4. Like most functions which wasn't built into DOS you needed to use a 3rd party util. Something as simple as CHKMEM would do the trick but I always preferred to use a system info program such as CheckIt Diagnostics or even Microsoft Diagnostics which I think appeared in MS-DOS 5 but is backwards compatible as far as I know although the lowest I've used it on is 3.21 on my XT's.

Come to think of it, do you have an IBM Diagnostic disk as part of the software you have? I'm not 100% but it may be able to give you the information you require.

Quote:
Originally Posted by sonicthemouse View Post
Edit: Also, would the add-in RAM be slower than the on-board RAM? Obviously these days the speed of the bus between the CPU and RAM is orders of magnitude faster than the "slot card" bus but perhaps going back through time this was not always the case?
No difference as at the end of the day you are limited to an 8088 processor. I don't think it really became a concern until a little later in PC development.


Are you planning on doing any preventative maintenance on the 5150? Reason I ask is from experience (and from what I've heard from others) with these things pushing 35 years since there release, a lot of the components are reaching end of life and failures will become more common. The old Tantulum caps for example have a nasty habit of going POP! and are found on just about everything. No real biggie if they fail as they will just create a short so you just replace it and it's all good again, but it's something to keep in mind to replace to prevent it from happening in the first place.

The other thing is the RIFA safety cap in the PSU. These things are notorious for dying in older PSU's and I believe there is also one in the CRT as well. When they blow they spew their contents all over the inside of the PSU and create such a stink and smoke cloud that it takes hours to go away. As you might of guessed I've been in the presence of one blowing. Scared the shit out of me with the noise it made and smoke spewing out! Good idea to replace them with more reliable modern polyester caps.

Not trying to scare you but I think it is something you need to think of when you are dealing with PC's (or any electronics for that matter) of such vintage.
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Old 29th April 2017, 9:53 PM   #58
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Australian Made!

image
Tad off topic, but...



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Old 17th May 2017, 11:53 PM   #59
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I'm sorry: I'm rather late to the party, but I'm contemporaneous with that machine I can shed some light on some of your questions.

Stunning find there! You bastard

Some off-the-top-of-my-head observations.
1: That's an IBM PC, not a PC/XT. It will have Cbasic (Cassette Basic) in ROM, and if you removed the HDD controller it should boot to that, just like Commodore 64's and the like - complete with "READY" prompt. Yes, you CAN hook up a cassette tape to the "Cassette" port and save to/load from it!

This also explains why there is no count during the RAMtest. That is normal for the PC. The XT introduced the RAM count.
2: The Hard drive is not original - it's an NEC DC-servo (Fast stepper) from about 1988: probably 10Meg. You'll find a toothed wheel on the outside of the stepper and a solenoid-driven locking spike (I worked as an engineer for an NEC dealership in the early 90's). FWIW those things were fucking bulletproof - I reckon they'd work underwater! It does not surprise me in the least that some 30 years later it still runs. Scour the internet for a program called "home.com" - it's a tiny TSR that parks the hdd after 10 seconds of inactivity. It needs it. PARK.COM is another one. Run it prior to shutting down the system.

The Hard drive controller will be some kind of third party and they were often unmarked. To determine who made it, run the MSDOS command "debug" - and from the debug prompt type in "d c800" "d" at the prompt again continues through ROM. It dumps the HDD controller ROM and you'll see the ID strings buried in there.
the command "g=c800:5" is usually the low-level format entry point. Mosttimes it prompts you before going ahead.

Sometimes not. My advice is not to find out.

That 83W power supply is underrated: It should have been replaced with a more powerful one when the HDD was put in. You're well and truly on the ragged edge now. IBM made a 120W PSU as a drop in replacement.

The video card also is not original. In fact YOU HAVE TWO! - WHOOPIE!.
There is some weirdness going on: you have one MDA card (the left most, looking at the second picture). That'll likely be the Taxan (I thought Taxan only made CRT monitors???). It also has an analogue joystick header.
The SECOND multifunction card ALSO capable of monochrome output (probably 16K hercules compatible - bringing dot-addressable 2-colour graphics). The second card has an RTC (Real Time Clock), complete with leaking battery(! - cut it out pronto!) and probably is the one that has the 384K RAM expansion. Like the first it has centronics parallel port, but also has an RS-232 port.(option for two - they'll be an empty socket for a spare 8250, and possibly two small 14 pin chips (1488/1489 pair) as RS232 drivers.

You cannot have two MDA cards on the one system as the mapping of video RAM for both occupies 4K (16K for Hercules) from $A000:00, so the the SECOND card must/should have the MDA card disabled.

Yes, the connector on the back of the FDC is for external floppies. It's not widely known but you can drive 4 Floppy drives in a PC and PC/XT. (Not AT or later). There will be a removable resistor terminator block close to the connector which is removed if the connector is used. (I've never seen it used - EVER)

Given a bit more time (and better photographs) I can probably tell you more, but that's what I can make out at first blush.

Oh, be VERY careful with the floppy drive - they're terribly sensitive to ESD. Actually make that the whole bloody system.

Once again, awesome catch!

Callan
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Last edited by callan; 18th May 2017 at 12:38 AM. Reason: Tidy up
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