You'll have to consult the manual. The earlier 486 boards with the soldered CPUs could sometimes only take PGA chips with a 487 pinout (i487sx, overdrive ODP or 3rd party upgrade with a 487SX jumper), but it looks like your board uses a 238 pin socket, which in my opinion is a good sign that it can take normal 486 chips. 3V chips like DX4 and 5x86 will still require a VRM of course. This system is from 93, so unlikely it supports 3.3V out of the box.

BTW, nice CDU-33A.

Anonymous Coward wrote:

You'll have to consult the manual. The earlier 486 boards with the soldered CPUs could sometimes only take PGA chips with a 487 pinout (i487sx, overdrive ODP or 3rd party upgrade with a 487SX jumper), but it looks like your board uses a 238 pin socket, which in my opinion is a good sign that it can take normal 486 chips. 3V chips like DX4 and 5x86 will still require a VRM of course. This system is from 93, so unlikely it supports 3.3V out of the box.

BTW, nice CDU-33A.

Yes, This is strange. I never seen a Media Vision PAS16 sound card with a Sony CDROM drive.
Usually they are 50 pin SCSI.

What driver do you think will work with this Sony CDROM drive ?
I don’t know if this CDROM is working correctly.
The CDROM activity LED stays on all the time.
And the exact button does not work.
I don’t know if the driver needs to be loaded for the CDROM drive to eject ?

The light is normally green when the drive is not reading a disc. It will turn orange if there is activity.
I can't seem to recall how the eject button works, but the tray is spring loaded (not motorized), however the eject button is electronic not mechanical. I think it should eject the disk as long as there is power. It was fairly common for the eject mechanism to break on these drives, but it is serviceable.

I think the name of the driver is SLCD.sys.

I recently uploaded the Sony CD drivers to vogonsdrivers.

Here is the sound card hardware.
It’s a Media Vision PAS 16 SL edition.
And a Sony CDROM drive. ( CDU31A )

What software package do I need to get this to work.
I currently have a hard drive loaded with DOS 6.22

I do not currently have the CDROM or sound card working.

I always thought that the CDU31A was a 1X model, but the computer label claims to have a 2X drive.

BTW, I found the service manual, but it costs $5.

https://www.nodevice.com/service-manuals/dvd- … du31a-st#lang-n

I inserted some CPU’s in this computer but was only able to get one to work.
I tried AMD 5x86 and Intel 50mhz, and Cyrix 66mhz. But none would work.
The only one that worked was a 486dx2-33mhz.
So do you think an Intel 486dx2-66mhz should would also ?

Well, to disable the onboard CPU you should probably have to set a jumper. Did you do that first?

http://www.uncreativelabs.de/th99/m/A-B/31980.htm

Use this. If the upgrade jumpers are set to "None" it should use the onboard CPU. Set it for the DX2 chip if you want to install a DX or DX2. The 5x86 should only be used with a voltage regulator.

Anonymous Coward wrote:

Well, to disable the onboard CPU you should probably have to set a jumper. Did you do that first?

http://www.uncreativelabs.de/th99/m/A-B/31980.htm

Use this. If the upgrade jumpers are set to "None" it should use the onboard CPU. Set it for the DX2 chip if you want to install a DX or DX2. The 5x86 should only be used with a voltage regulator.

Thanks, That Motherboard diagram is what I needed to know.

Anonymous Coward wrote:

Well, to disable the onboard CPU you should probably have to set a jumper. Did you do that first?

http://www.uncreativelabs.de/th99/m/A-B/31980.htm

Use this. If the upgrade jumpers are set to "None" it should use the onboard CPU. Set it for the DX2 chip if you want to install a DX or DX2. The 5x86 should only be used with a voltage regulator.

Okay, I reset the jumpers for an Overdrive 486dx2@50mhz. and put in an Intel 486dx2-50
It works but now I can't get the computer to recognize the hard-drive.

Is a 486dx2-50 CPU good enough for DOS gaming and Multimedia cdroms or do I need a 486dx2-66mhz CPU ?

It depends on what you're going to be running. I'd say a DX-33 would let you run most DOS stuff up to about 1995, but after that there were DOS games that started needed Pentium power. A lot of the early multimedia titles were just regular VGA games with voice tracks tacked on on, but I managed to run quite a few FMV games on my DX-33 too. The 7th Guest for example ran at full speed as far as I could tell.
IF you want to run Fade to Black, Mechwarrior II or Syndicate Wars in DOS, I don't really know that any 486 would run those very well.

Anonymous Coward wrote:

It depends on what you're going to be running. I'd say a DX-33 would let you run most DOS stuff up to about 1995, but after that there were DOS games that started needed Pentium power. A lot of the early multimedia titles were just regular VGA games with voice tracks tacked on on, but I managed to run quite a few FMV games on my DX-33 too. The 7th Guest for example ran at full speed as far as I could tell.
IF you want to run Fade to Black, Mechwarrior II or Syndicate Wars in DOS, I don't really know that any 486 would run those very well.

Yes, from what I remember from my Original 1993 PC was that the 2x CDROM and 4mb of ram was the bottle neck.
The 2x CDROM was always seeking and would play CDROM disk very slow.
I want to stay period correct on this 1993 computer so I think the 486dx2-50 CPU upgrade is okay.
Along with 16mb of ram and a 540 hard-drive.
This computer only has 64kb of cache and It has some funky cache module upgrade slots.
I don't have any kind of this cache on hand.
Is 64kb of cache going to be a problem for a multimedia computer ?

Well, 64k is fine for 8MB of RAM, but for 16MB it would be preferrable to have more. I doubt you'd notice much of a difference though. 64kb is still much better than 0kb. My dx-33 only had 64kb cache, and it was fine.

The 2X CD-ROM drives do indeed seek quite a lot. The Sony drive you have is a budget model. While not the worst drive, you'd probably have a much smoother experience with a 2X SCSI drive like an NEC. My biggest regret from back then was wasting money on a Creative CD-ROM kit, rather than just buying a SCSI 2X drive and a cheap controller. Don't you find the seeking sound of the CDU 31A super annoying?

Also, I looked into the CDU-31A. Although almost all of them were 1X drives, I saw a few references to some of them being 2X drives as well. Yours is a -02 model, so I assume it must be a 2X model. It seems to be the one that came with the computer.

Anonymous Coward wrote:

Well, 64k is fine for 8MB of RAM, but for 16MB it would be preferrable to have more. I doubt you'd notice much of a difference though. 64kb is still much better than 0kb. My dx-33 only had 64kb cache, and it was fine.

The 2X CD-ROM drives do indeed seek quite a lot. The Sony drive you have is a budget model. While not the worst drive, you'd probably have a much smoother experience with a 2X SCSI drive like an NEC. My biggest regret from back then was wasting money on a Creative CD-ROM kit, rather than just buying a SCSI 2X drive and a cheap controller. Don't you find the seeking sound of the CDU 31A super annoying?

Also, I looked into the CDU-31A. Although almost all of them were 1X drives, I saw a few references to some of them being 2X drives as well. Yours is a -02 model, so I assume it must be a 2X model. It seems to be the one that came with the computer.

Yes, going from 64kb to 256kb does help performance by about 5%
However going from 256kb to 512kb does not help much.