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What am I doing with a 286?

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First post, by probnot

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I seem to be getting older and older systems. This one was too good a deal to pass up. Came with a sweet AT keyboard as well (proper mechanical, not rubber dome). Another brand I remember from when I was a kid.... Laser!! (Warning: lots of pics ahead)

Specs:

-Laser AT Clone Case
-286 10Mhz
-640k RAM
-41MB Seagate ST-251 MFM HDD (not working)
-3.5" 1.44mb Floppy
-5.25" 1.2mb Floppy
-Unknown full-length CGA or EGA card
-Serial/Parallel port I/O card
-Western Digital WD1003-WA2 MFM/Floppy controller card

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I opened it and thoroughly cleaned out the dust. Overall it was pretty clean for its age.

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Also removed what was left of the leaky CMOS battery. It looks like it exploded at some point in its life (there were blue remnants of the outer case all over). Luckily the previous owner had installed an external battery holder, and the batteries it came with are still ok!

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I don't have any monitors to plug into this (pretty sure the card is either CGA or EGA), but I do have a Commodore monitor that works OK using the composite output. I was surprised to get colour on this, I thought the RCA outputs were always mono on these cards (maybe only mono at high res?)

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What Win Lose or Draw is supposed to look like:
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What it looks like on the Commodore 1702:
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Now I need to figure out how to verify if this MFM drive is dead. I haven't touched one of these in like 25+ years, so I'm not even sure where to start.

Reply 1 of 29, by gdjacobs

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I'd be tempted to substitute an ATA drive for simplicity. Also, upgrade to 286-16 and FPU?

All hail the Great Capacitor Brand Finder

Reply 2 of 29, by probnot

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gdjacobs wrote:

I'd be tempted to substitute an ATA drive for simplicity. Also, upgrade to 286-16 and FPU?

I was thinking that, since this old 42mb drive is definitely bad. I have an ATA/Floppy/IO card kicking around from the first 486 that isn't doing anything.

Also have Intel 286-12 and Harris 286-20 chips kicking around. How easy would changing that be? I have no idea what motherboard this is, so I don't know the jumper settings.

Reply 3 of 29, by luckybob

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probnot wrote:
gdjacobs wrote:

I'd be tempted to substitute an ATA drive for simplicity. Also, upgrade to 286-16 and FPU?

I was thinking that, since this old 42mb drive is definitely bad. I have an ATA/Floppy/IO card kicking around from the first 486 that isn't doing anything.

Also have Intel 286-12 and Harris 286-20 chips kicking around. How easy would changing that be? I have no idea what motherboard this is, so I don't know the jumper settings.

it's not worth the effort. Long story short, you would have to replace the OSC2 crystal with something faster.

Can it be done? yes. Is it worth the effort? hardly. The mobo might not accept the new speed. If you need something faster, it's just good practice to buy a faster system.

It is a mistake to think you can solve any major problems just with potatoes.

Reply 4 of 29, by Jo22

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I agree with that. No that is a bad idea to upgrade the machine massively, but..
Well, I think it is fine the way it is. A 286-10 or 286-12 is a sweet spot for playing CGA games
a little bit smoother, but not too fast to make them unplayable.

However, as a 286 fan (sort of) I would suggest to install a cheap 287XL-like FPU and/or an EMS card.
The EMS card comes in handy for DESQView, disk caching programs and CAD tools (AutoSketch 3.x) and
other useful programs (antivirus, Windows 3.0 Real-Mode) and games from late80s/early90s (some Sierra games use EMS).
The math-copro is useful for zip programs, mandelbrot generators and a few games like SimCity.

And last, but not least, I would suggest to have at least 2-4MiB of Extended Memory (for XMS),
I you're going to run Windows 3.x in Standard-Mode on that machine.
XMS can be provided by ISA memory boards, like those from AST (some Rampage models), Quadram, Megalith.
http://th99.classic-computing.de/src/i/imem_1.htm

Anyway, that's just my opinion. Sometimes these things can be found cheaply on places like eBay,
since it is not so sought after, like say a Voodoo3.

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 5 of 29, by mrau

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Jo22 wrote:

I agree with that. No that is a bad idea to upgrade the machine massively, but..
Well, I think it is fine the way it is. A 286-10 or 286-12 is a sweet spot for playing CGA games
a little bit smoother, but not too fast to make them unplayable.

machines back then could not be clock adjusted on the fly? i remember fast 286 were faster than slow 386 in 16 bit software at times; i miss the times when this was geek territory;

Jo22 wrote:
However, as a 286 fan (sort of) I would suggest to install a cheap 287XL-like FPU and/or an EMS card. The EMS card comes in hand […]
Show full quote

However, as a 286 fan (sort of) I would suggest to install a cheap 287XL-like FPU and/or an EMS card.
The EMS card comes in handy for DESQView, disk caching programs and CAD tools (AutoSketch 3.x) and
other useful programs (antivirus, Windows 3.0 Real-Mode) and games from late80s/early90s (some Sierra games use EMS).
The math-copro is useful for zip programs, mandelbrot generators and a few games like SimCity.

zip used the fpu? 😮 so how was lossless compression guaranteed then? i always thought these 2 things were incompatible;
any idea how simcity made use of the fpu? this thing ran very well on my dx40, fpu back then was slow though... any comparison/info on how fpu improved the simcity experience?
can the same memory cards provide ems and xms? in that case ram could stay at 1mb is that correct?
any idea how much ems/xms was required/handy for these programs? someone here had a machine with 32mb hard EMS iirc; i often thought this technology was dropped too soon; (might have been handy till early duron era imho);

Reply 6 of 29, by probnot

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luckybob wrote:

it's not worth the effort. Long story short, you would have to replace the OSC2 crystal with something faster.

Can it be done? yes. Is it worth the effort? hardly. The mobo might not accept the new speed. If you need something faster, it's just good practice to buy a faster system.

That's what I remember reading in the past. I'll leave it as is.

One problem I've run into is getting it to place nice with my IDE to SD adapter. I replaced the MFM controller and IO cards with a PT-604A IO Card from an unused 486. This bios doesn't support manually entering the Cyl/Heads/Sector info manually. It has types 1 thru 47, but 41-47 are empty. I'm suspecting the it would need to be re-flashed to modify one of the empty drive types... I was able to "sort of" get 32MB and 256MB cards working, but they end up with odd problems.

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Jo22 wrote:
However, as a 286 fan (sort of) I would suggest to install a cheap 287XL-like FPU and/or an EMS card. The EMS card comes in hand […]
Show full quote

However, as a 286 fan (sort of) I would suggest to install a cheap 287XL-like FPU and/or an EMS card.
The EMS card comes in handy for DESQView, disk caching programs and CAD tools (AutoSketch 3.x) and
other useful programs (antivirus, Windows 3.0 Real-Mode) and games from late80s/early90s (some Sierra games use EMS).
The math-copro is useful for zip programs, mandelbrot generators and a few games like SimCity.

And last, but not least, I would suggest to have at least 2-4MiB of Extended Memory (for XMS),
I you're going to run Windows 3.x in Standard-Mode on that machine.
XMS can be provided by ISA memory boards, like those from AST (some Rampage models), Quadram, Megalith.
http://th99.classic-computing.de/src/i/imem_1.htm

I found this sucker, but installing it did nothing but add a beep code at post (system still booted OK).

hzfdUKtl.jpg

I tried removing the 41256 chips from it and replacing the 4164 chips in the 2nd two banks on the motherboard, which gave me 1024k total, but even with the jumpers changed, it gives me a memory size error. Anything I'm missing here?

Motherboard info: http://www.arvutimuuseum.ee/th99/m/I-L/33690.htm (mine is Ver.C but looks identical to this, same jumper and pin config)

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Reply 8 of 29, by gdjacobs

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mrau wrote:

machines back then could not be clock adjusted on the fly? i remember fast 286 were faster than slow 386 in 16 bit software at times; i miss the times when this was geek territory;

IIRC, the CPU ran synchronous with the crystal. Adjusting the clock speed would likely need a PLL chip. This would be an interesting project, although even more involved than a straight CPU and crystal upgrade.

All hail the Great Capacitor Brand Finder

Reply 9 of 29, by Jo22

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mrau wrote:
Jo22 wrote:

I agree with that. No that is a bad idea to upgrade the machine massively, but..
Well, I think it is fine the way it is. A 286-10 or 286-12 is a sweet spot for playing CGA games
a little bit smoother, but not too fast to make them unplayable.

machines back then could not be clock adjusted on the fly?

It depends on the machine, I guess. Not all of them had NEAT-like chipsets.
Also, some used wait-states for "turbo" instead of actually changing clock frequency.
And some machines had ISA-speed coupled with CPU-speed, because ISA was more or less directly wired to the processor.
Bye the way, this is an interesting aspect of early 286 motherboards..
Machines made before, say ~88, did pre-date ISA specs. So technically speaking, they had AT-Bus slots at the time.
And because of the lack of these specs, early but higher-end 286 PCs often supported notable BUS speeds of 10/12/16MHz,
before ISA lowered it down to depressingly ~8MHz.
Evidences for this can still be found on ancient RAM boards, which often claim to support 12MHz operation.
https://en.wikipedia.org/wiki/Industry_Standa … ying_bus_speeds

mrau wrote:

i remember fast 286 were faster than slow 386 in 16 bit software at times; i miss the times when this was geek territory;

Yes, I believe that's true. The 286 supported ISA natively, while the 386SX needed a bit of external electronic.
By the way, something to comes to my mind: The 386DX did also support 16bit/24Bit operation. In theory, it could do all the stuff the 386SX could do.
If I'm not mistaken, some older magazines of the time even said the SX was a lame, useless invention made by Intel.

mrau wrote:

zip used the fpu? 😮 so how was lossless compression guaranteed then? i always thought these 2 things were incompatible;
any idea how simcity made use of the fpu? this thing ran very well on my dx40, fpu back then was slow though... any comparison/info on how fpu improved the simcity experience?

Sorry, I meant EMS. Pkunzip does support different porcessors, though. As for SimCity, I think it did help quite a bit.
The whole simulation was very number-heavy, afterall. Another game supporting FPUs might be SimEarth, but I'm not sure.

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mrau wrote:

can the same memory cards provide ems and xms? in that case ram could stay at 1mb is that correct?
any idea how much ems/xms was required/handy for these programs? someone here had a machine with 32mb hard EMS iirc; i often thought this technology was dropped too soon; (might have been handy till early duron era imho);

Hi, EMS cards are cool, I think. 😀 I've got an AST Rampage 286 W/ 2MiB and I can't complain. It worked with everything EMS so far (upto LIM4, EEMS 3.2).
The card comes with its own driver, remm.sys, and is independend of the main memory.
At least in EMS mode (still have to try XMS mode), there's no need to touch any of the memory chips on the 286 motherboard.
From a personal experience, it can even be installed in 386/486/586 machines without problems (in EMS mode).
And most games I've played so far, did never ask for more than 2 Megabyte of EMS. So I think that's fine for most stuff.
If you'e curious about hardware EMS, have a look at https://www.lo-tech.co.uk/wiki/Lo-tech_2MB_EMS_Board
While I haven't had a chance to try the card myself (currently out of stock), I assume it works similar to the old Rampage.
Except for using an 8Bit slot, instead of the Rampage's 16Bit connection. But on the other hand, the LoTech board uses much quicker RAM.. 😉

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 10 of 29, by Jo22

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probnot wrote:

Nevermind the memory issue... changing the Base/Extended to 512/512 fixed it!

Whew! Glad it worked! 😁 These XT RAM cards (or UMB cards - both are essentially the same) can be quite finical at times.
I own one of these, too, and without the manual I'd be totally lost! 😅

By the way, If you ever run out of HDD space, just use an IDE controller and XTIDE Universal BIOS (AT) (see here).
It worked liked a charm in the last 286 I worked on. It also has the advantage of booting from a Secondary-Master drive.
Provided, that the soundcard / IDE card has jumpers for enabling the IDE portion. Later PnP cards require lousy tools like CTCU. 😢
And last, but not least, the Universal BIOS doesn't require extended memory for storing the parameters.
- That IDE Enhancer card I've tried before complained about no available storage space.

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 11 of 29, by probnot

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Jo22 wrote:
Whew! Glad it worked! :D These XT RAM cards (or UMB cards - both are essentially the same) can be quite finical at times. I own […]
Show full quote
probnot wrote:

Nevermind the memory issue... changing the Base/Extended to 512/512 fixed it!

Whew! Glad it worked! 😁 These XT RAM cards (or UMB cards - both are essentially the same) can be quite finical at times.
I own one of these, too, and without the manual I'd be totally lost! 😅

By the way, If you ever run out of HDD space, just use an IDE controller and XTIDE Universal BIOS (AT) (see here).
It worked liked a charm in the last 286 I worked on. It also has the advantage of booting from a Secondary-Master drive.
Provided, that the soundcard / IDE card has jumpers for enabling the IDE portion. Later PnP cards require lousy tools like CTCU. 😢
And last, but not least, the Universal BIOS doesn't require extended memory for storing the parameters.
- That IDE Enhancer card I've tried before complained about no available storage space.

I'm not sure I like running it with 1mb on the motherboard. If I set the jumper to 640k, I get 640k conventional/0k extended. But if I set the jumper to 1024k, I get 512k conventional/512k extended. So I lose 128k conventional...

I would have assumed I would get 640k/384k. I may search for a memory card that has documentation, etc.

Reply 12 of 29, by Jo22

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probnot wrote:

I would have assumed I would get 640k/384k. I may search for a memory card that has documentation, etc.

You're right - That's how it is supposed to be. I am not sure as to why your machine behaves so differently.
On the bright side, there were a lot of no-name 128KiB upgrade cards which were meant for 512KiB system. ^^
In fact, the UMB card that I own possesses exactly this default setting. It is wired for XT class machines
with only 512KiB of random access memory. Too bad my XT clone already has 640KiB of memory.. 🙁

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 13 of 29, by Jo22

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Oh, there's something I forgot to mention! You can actually use a Hercules card to get 64KiB of UMBs.
Since you're running a CGA system, it would perhaps not conflict with your video memory (if Hercules is set to half-mode).

Together with the extra memory in the HMA (High Memory Area), you could compensate for the loss of 128KiB of base memory.
Just load DOS 5 or 6.xx high and/or into the UMBs provided by the Hercules card (DOS=HIGH, UMB).

Anyway, it's just an idea. I was trying to get that thing working some time ago, but was not successful.
Perhaps because I was using a Hercules clone card without a real Motorola video processor.

So if you've got a spare Hercules Monochrome Card, or Hercules Plus, you may want to give it a try.

You can read my misadventures in this thread: Umbherc.sys requirements ?

Edit: Just noticed your VTech graphics card could be newer than CGA (-> has its own ROM chip for BIOS or font)..
Edit: Also, on some photos your BIOS Setup is set to MONO (= MDA, Hercules). Maybe changing it to COLOR fixes things ? 😀
Edit: OK, you already set it to EGA. I should really consider to stop writing stuff at midnight.. 😅

Last edited by Jo22 on 2017-08-28, 22:57. Edited 1 time in total.

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 14 of 29, by kixs

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probnot wrote:
Jo22 wrote:
Whew! Glad it worked! :D These XT RAM cards (or UMB cards - both are essentially the same) can be quite finical at times. I own […]
Show full quote
probnot wrote:

Nevermind the memory issue... changing the Base/Extended to 512/512 fixed it!

Whew! Glad it worked! 😁 These XT RAM cards (or UMB cards - both are essentially the same) can be quite finical at times.
I own one of these, too, and without the manual I'd be totally lost! 😅

By the way, If you ever run out of HDD space, just use an IDE controller and XTIDE Universal BIOS (AT) (see here).
It worked liked a charm in the last 286 I worked on. It also has the advantage of booting from a Secondary-Master drive.
Provided, that the soundcard / IDE card has jumpers for enabling the IDE portion. Later PnP cards require lousy tools like CTCU. 😢
And last, but not least, the Universal BIOS doesn't require extended memory for storing the parameters.
- That IDE Enhancer card I've tried before complained about no available storage space.

I'm not sure I like running it with 1mb on the motherboard. If I set the jumper to 640k, I get 640k conventional/0k extended. But if I set the jumper to 1024k, I get 512k conventional/512k extended. So I lose 128k conventional...

I would have assumed I would get 640k/384k. I may search for a memory card that has documentation, etc.

I have kinda the same thing with memory configuration on this board:
http://imgur.com/KJAHH5R

I can configure it as 640KB + 0KB EXT or 512/512. Can't find the setting for 640 + the rest.

Requests are also possible... /msg kixs

Reply 15 of 29, by probnot

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kixs wrote:

I have kinda the same thing with memory configuration on this board:
http://imgur.com/KJAHH5R

I can configure it as 640KB + 0KB EXT or 512/512. Can't find the setting for 640 + the rest.

I wonder if it's due to the configuration of memory banks? 640k=256+256+64+64, so it can be lumped together. But 1024=256+256+256+256, so splitting it into 640k and 384k might be something these older 286 boards can't handle...Either way, I guess the solution will be trying to find a memory card.

Also, to add: I borrowed an ISA IO card (IDE/Floppy/etc) from a 486 and installed a Seagate 40gb hdd with overlay software (smallest reliable IDE drive I have at the moment). Boots up great with a 2gb partition. I wanted to use my CF-IDE adapter (which works flawlessly with this IO card on my 486) but I just had too many issues handling larger files.

I also swapped out the newer floppy drive for one more age appropriate. Colour matches and the stepper motor has nice loud hum to it (also I like the red LED). Since the newer floppy drive is the same make as the broken one in my PIII, I swapped the black and white bezels and put it in that PC 😀

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Next step is find a VGA card and memory card. I'm sick of composite quality CGA already 🤣

Reply 16 of 29, by Jo22

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Next step is find a VGA card and memory card. I'm sick of composite quality CGA already

That's understandable. :) If the current EGA (?) graphics card can't do proper Composite CGA then there's little practial reason to keep that card installed,
since some early VGA cards have emulation modes for things like CGA RGB, EGA, Hercules, Olivetti, etc. (PVGA/Trident 8x00/ET3K/ET4K/..)
and are much faster. Also, they don't have scrolling issues with certain titles (Keen IV) and enought video memory to do 640x350 in full colour.

In case you want to keep the 1702 in use, there are converters for VGA -> Composite. Here's a sample link of such a device on Amazon: link
But be warned - I have never tested that model. My whole experience is solely based on that ancient VGA cheese..

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 17 of 29, by probnot

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Jo22 wrote:
That's understandable. :) If the current EGA (?) graphics card can't do proper Composite CGA then there's little practial reason […]
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Next step is find a VGA card and memory card. I'm sick of composite quality CGA already

That's understandable. 😀 If the current EGA (?) graphics card can't do proper Composite CGA then there's little practial reason to keep that card installed,
since some early VGA cards have emulation modes for things like CGA RGB, EGA, Hercules, Olivetti, etc. (PVGA/Trident 8x00/ET3K/ET4K/..)
and are much faster. Also, they don't have scrolling issues with certain titles (Keen IV) and enought video memory to do 640x350 in full colour.

In case you want to keep the 1702 in use, there are converters for VGA -> Composite. Here's a sample link of such a device on Amazon: link
But be warned - I have never tested that model. My whole experience is solely based on that ancient VGA cheese..

No plan on keeping the 1702 hooked up (though it is a sweet little monitor). I have some VGA->composite adapters (also a composite to VGA adapter). My plan is to hook this into my KVM.

Reply 18 of 29, by Jo22

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Cool! You've got my best wishes. Hope you get that memory card soon, too. ^^

probnot wrote:

(though it is a sweet little monitor)

Yup, I had the almost same model as a kid (PAL). ^_^ Long, long ago my dad gave it to me and so it became my Nintendo monitor (NES+SNES).
It did a good job for composite video, maybe because of comb filters, dunno. The controls were also cool, to fix PAL borders.
Still don't get it why there's so much of a cult in respect of this model now. I've seen television sets with softer visual presentation also.
Edit: I also honour the 170x series for beeing 100% analogue. These video monitors are reliable and can't be confused by oddball video formats.

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 19 of 29, by probnot

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Jo22 wrote:
Cool! You've got my best wishes. Hope you get that memory card soon, too. ^^ […]
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Cool! You've got my best wishes. Hope you get that memory card soon, too. ^^

probnot wrote:

(though it is a sweet little monitor)

Yup, I had the almost same model as a kid (PAL). 😄 Long, long ago my dad gave it to me and so it became my Nintendo monitor (NES+SNES).
It did a good job for composite video, maybe because of comb filters, dunno. The controls were also cool, to fix PAL borders.
Still don't get it why there's so much of a cult in respect of this model now. I've seen television sets with softer visual presentation also.
Edit: I also honour the 170x series for beeing 100% analogue. These video monitors are reliable and can't be confused by oddball video formats.

All things considered, the text is crisp and sharp for a composite signal. I found that connecting both composite outputs from the video card to the chrominance and luma inputs on the monitor yields better results (even though video card outputs the same combined signal on both outputs)...