The box

Intel486dx33 wrote on 2021-09-02, 01:41:

BLockOUT wrote on 2021-08-25, 23:34:

Intel486dx33 wrote on 2021-08-25, 23:06:

See my posts above with the manual white pages. It shows the jumper settings for 486dx2. Use that jumper setting for 33mhz. CPU […]
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See my posts above with the manual white pages.
It shows the jumper settings for 486dx2.
Use that jumper setting for 33mhz. CPU
Or maybe it was the Pentium overdrive CPU setting.

You need to switch the jumpers for 286kb of cache too when used.

See photos above.

Update:
Actually, your motherboard is different from mine.
I don’t see your motherboard in the hardware manual.

Look on the back of your computer and see the “Machine type model”
It’s something like “2255”

Then search the internet for that model type manual.

interesting , in the manual you posted today that motherboard model from our pictures is not included in the manual designs.
but if you say that setting the board jumpers to overdrive...will also work with a dx2 66mhz and a transposer i might give it a try.

I am going to try one of these in my other PS/1 with a 486sx-33. It has an Intel Overdrive socket but only excepts 169-pin CPU’s
So this adapter with a 486dx4-100 should work.

please let me know if it works, test it leving the pc on for 20 minutes to see if it glitches or hangs

BLockOUT wrote on 2021-09-14, 15:31:

Intel486dx33 wrote on 2021-09-02, 01:41:

BLockOUT wrote on 2021-08-25, 23:34:

interesting , in the manual you posted today that motherboard model from our pictures is not included in the manual designs.
but if you say that setting the board jumpers to overdrive...will also work with a dx2 66mhz and a transposer i might give it a try.

I am going to try one of these in my other PS/1 with a 486sx-33. It has an Intel Overdrive socket but only excepts 169-pin CPU’s
So this adapter with a 486dx4-100 should work.

please let me know if it works, test it leving the pc on for 20 minutes to see if it glitches or hangs

Be aware. his person makes fake post about non existent systems he has. He gets pic of the internet and claims they are his systems

BLockOUT wrote on 2021-09-14, 15:31:

Intel486dx33 wrote on 2021-09-02, 01:41:

BLockOUT wrote on 2021-08-25, 23:34:

interesting , in the manual you posted today that motherboard model from our pictures is not included in the manual designs.
but if you say that setting the board jumpers to overdrive...will also work with a dx2 66mhz and a transposer i might give it a try.

I am going to try one of these in my other PS/1 with a 486sx-33. It has an Intel Overdrive socket but only excepts 169-pin CPU’s
So this adapter with a 486dx4-100 should work.

please let me know if it works, test it leving the pc on for 20 minutes to see if it glitches or hangs

Okay, I have that computer stored away in my garage so I will have to pull it out.

Intel486dx33 wrote on 2019-09-01, 13:00:

The 486 IBM PS/1 came preloaded with DOS and Win3.1 ( 16-bit operating systems ). Windows 95 was a 32-bit operating system. It w […]
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AlessandroB wrote:

Intel486dx33 wrote:

Yes, The 1993/94 IBM PS/1 came preloaded with DOS 6.21 and Win3.1 Windows 95 came out in 1995 and by that time the Pentium CPU w […]
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Yes, The 1993/94 IBM PS/1 came preloaded with DOS 6.21 and Win3.1
Windows 95 came out in 1995 and by that time the Pentium CPU was well available.
The IBM 350 came with a Pentium CPU and Win95.
https://en.wikipedia.org/wiki/IBM_PC_Series

you haven't reply at my post, the graphic and ide chip on the mainboard, are connected to the system in ISA or VLBUS??

The 486 IBM PS/1 came preloaded with DOS and Win3.1 ( 16-bit operating systems ).
Windows 95 was a 32-bit operating system. It was a different era in computing and hardware.
https://youtu.be/ZBbvmORcgSo

Some of the fastest video cards available for the VLB slot where the Cirrus Logic 5426, 5428 and 5429.
The 5430 was only available on PCI and was onboard on the 486 IBM 330 computer.

You still haven't replied to AlessandroBs question.........

AlessandroB wrote on 2019-09-01, 10:22:

Intel486dx33 wrote:

Yes, The 1993/94 IBM PS/1 came preloaded with DOS 6.21 and Win3.1 Windows 95 came out in 1995 and by that time the Pentium CPU w […]
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AlessandroB wrote:

Yes but is connected via the slow isa bus instead vlbus...

Yes, The 1993/94 IBM PS/1 came preloaded with DOS 6.21 and Win3.1
Windows 95 came out in 1995 and by that time the Pentium CPU was well available.
The IBM 350 came with a Pentium CPU and Win95.
https://en.wikipedia.org/wiki/IBM_PC_Series

you haven't reply at my post, the graphic and ide chip on the mainboard, are connected to the system in ISA or VLBUS??

This model ps/1 computer is all ISA. I am not sure If the onboard IDE controller is 32bit ?

Intel486dx33 wrote on 2021-09-16, 06:45:

AlessandroB wrote on 2019-09-01, 10:22:

Intel486dx33 wrote:

Yes, The 1993/94 IBM PS/1 came preloaded with DOS 6.21 and Win3.1 Windows 95 came out in 1995 and by that time the Pentium CPU w […]
Show full quote

Yes, The 1993/94 IBM PS/1 came preloaded with DOS 6.21 and Win3.1
Windows 95 came out in 1995 and by that time the Pentium CPU was well available.
The IBM 350 came with a Pentium CPU and Win95.
https://en.wikipedia.org/wiki/IBM_PC_Series

you haven't reply at my post, the graphic and ide chip on the mainboard, are connected to the system in ISA or VLBUS??

This model ps/1 computer is all ISA. I am not sure If the onboard IDE controller is 32bit ?

You have easy access to the IBM PS/1 series workshop manual so you should know.

I modified the Autoexec.bat file and loaded all the drivers “HIGH” in upper memory.
So its now working with only 3mb. Of Memory used in DOS 5.0.
But when I Start Win3x it loads all of the 32mb of Memory and that’s Okay.
What good is MEMORY if the computer is NOT using it Right ?
Thats how I see it.

So this modification Free’s up “Conventional memory” so I can play DOS games that require allot of Conventional Memory.

Are there any draw backs to loading device drivers HIGH ?….

The 486 Cadillac

Guys if there is ONE computer you need in your 1990’s collection this is it.
The IBM PS/1 model 2155 is the Cadillac of 486 computers.
This computer is loaded with all the Bells and Whistles.
I use the Original hard drive image from the 2155 Multimedia computer.
It’s loaded with Innovation, menus, batch files and scripts.
This is What Set IBM apart from all other computers.
They made the 486 computer so easy to use and administer.

Even if you have any 486 computer I would try this IBM 2155 Multimedia Hard drive image because it will open your mind and give you ideas on how a 486 computer should be setup and configured. It will give you some good ideas.
If you ever take a class in DOS you should definitely look at this hard drive image.
Just download and burn to CD. Then put in your 486 computer boot off a DOS floppy with CDROM support.
https://ps1stuff.wordpress.com/download/downl … -for-type-2133/

Format your C-drive And then copy the CD contents to you hard drive with xcopy command
E.g. A:\xcopy D:\*.* C:\
This command will copy the contents of your CD to your Hard drive.

Then you can edit these config files to better work with your 486 computer.

Minimum requirements:
486 CPU
4mb RAM
64kb cache
Sound Blaster
CDROM
VGA or SVGA video card

Here are some benchmarks of the Best mass produced Multimedia computer of 1993

My IBM out IBMs your IBM, PC330 6571 is the best IBM 486 😜

Yeah, What set IBM computers apart from Everyone else was there Software setup and configuration.
There installations were loaded with Menus, Batch files, backup and Recovery, Ease of Use.
They made their computers easy to use and administer like a Mac.

I was Wrong, its NOT a Cadillac but a Model-A

I tried to watch a Movie CD and it would not play. Too choppy.
I think the 486dx-50 CPU is too slow or it could have been the 2x CDROM, Not sure.

But my 486dx4-100 plays Video CD’s just fine.
Ironically my 486dx4-100 PC benchmarks exactly twice as high as this 486dx-50 computer.

Update:
I think it’s the Original CDROM drive that is too slow. It seeks allot to.

Testing Games.
It plays Doom too.

Now my Floppy drive combo is acting up and does NOT want to read drives.
I tried cleaning the heads with a Diskette cleaner but that did not work.
I will try to clean and re-seat the cables next.
Hope that fixes the problems because I am not done beating up this computer.
I want to do some more testing.
These are my favorite early IBM 486 computers because they are easy to fix and upgrade.

Okay, I fixed the floppy drives. Turned the ribbons connecting the two floppy drives needed to be re-seat.
I also benchmarked the computer.

With L1 cache Disabled I get a score of 65 in topbench
With L1 cache Enabled I get a score of 144 in topbench

For reference a 286@20mhz gets a score of 50
A 486dx4-100 gets a score of 219

So this computer can be slowed down to 286 speed by Disabling L1 cache using “Setmul” program.
This computer does NOT have a turbo button.

Some computers can have turbo mode turned ON or OFF using the keyboard. Not sure about this one ?