Is that a DX-50 or a DX2-50? Would be worth it to double-check. That "DX-66" of course has to be a DX2-66.

Yes,

5-volt
486dx-33
486dx2-50
486dx2-66

Actually, Now that I think about it. This Motherboard was allot like my first computer which was a Intel 486dx-33 with 4mb ram on a generic brand motherboard.

Go with the DX2-66 to have at least some headroom processor wise.

Since you're using a busspeed of 33 mhz, 20ns sram should be fast enough, but as always - testing is necessary. FPM vs EDO is more of an "economy" thing as former is often easier to get. You're board seems to support 30 pin simms which may automatically render EDO modules most likely a non option.

Regarding the tag ram - you're most likely stuck with 128 a 4 x 32K due to it being an old board(manual knows more) so your 32k tag is more than enough(a 16K tag "supports" up to 512K cache).

What are you using that machine for?

not sure what you are aiming for, but I just finished a build using a isa only 486 5v board which was 486dx50 stock and currently running a 586 133 3v clocked to 160mhz through a voltage converter.

I am not sure but if you add more cache I think you may need to increase the cache tag ram chip to match

Intel486dx33 wrote:

I want to build a 486 computer using only ISA cards. I purchased this NEW old Stock motherboard. I think it only supports 5v CPU […]
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I want to build a 486 computer using only ISA cards.
I purchased this NEW old Stock motherboard.
I think it only supports 5v CPU's

So I can use a

486dx-33
486dx-50
486dx-66

These are the Socket-3 CPU's I have on hand.

What ram should I use for best performance and at what speed ?
EDO or Fast page ?
What speed ?

Also it has -20 cache modules installed. Looks like 128kb.
Is this okay ?

I have ISA controller, SVGA graphics card and Sound blaster 16/AWE64 or Yamaha or Media Vision with Yamaha OPL support card.
Network 3com 3c509. I can add multiple sound cards for OPL support.

What would you recommend ?

A lot of the older motherboards will only work with Fast page. EDO is a very late 486, mostly 2nd gen pentium (90Mhz and onwards). ~60ns should be fine for a 486.

Obviously the DX2-66 will be the fastest but for games you'll be limited by the isa graphics card, you'll need a fast one BTW. About cache what for? 128 KB is fine for that isa board. Pretty cool board BTW, if i remember right the symphony chipset was fast.
Of course no EDO support, and actually EDO ram is more common than FPM.

Expect the battery in that Dallas RTC (DS1287) to be flat (dates from 1992, week 18 😀), which means you'll constantly loose CMOS (BIOS) settings if switched off for extended periods.
You can either:
1.) find a suitable replacement on eBay (make sure the year of manufacture is fairly recent) or,
2.) see if your motherboard has an external battery connector (doesn't appear to have) or,
3.) go the mod route by using a dremel (refer http://pc-restorer.com/replacing-cmos-batteries-in-old-pcs/).

However, I agree that EDO RAM will mostly likely not work on this motherboard.

Okay,
So I just want this computer for DOS games and maybe Win3.11 too ( Dual boot )
I will use a CF adapter with 8gb CF card. for storage. ( hard-drive )

So I will go with EDO ram, But how much can I add to this motherboard ?
It has 8 simm slots.

I will need to find a Clock battery solution. replace or modify ?

Cache is good

Intel 486dx2-50 CPU. ( 5 volts ).

What speed CDROM should I use ?

win 3.11 was only dual boot, boot to dos then manually launch win, unless you set it up in autoexec.bat to do auto

If you use a large cf card you will have to partition and format it to a smaller size. Fat is 2gb max and so is dos 6.22, dos 7 will read a 4gb partition.
It also depends on your bios/ide controller card how much it will see.
For example on my 486 the bios will see my whole 2gb cf card but my ide controller card will only see 502mb which results in alot of sector errors.

So first figure out what your bios/controller card will handle go with 502mb if you want to be safe, probably about right for that time.

Find a manual for your motherboard to see the max ram it will take. Look up the bios strings, board name on google

3 solutions for bios battery
1. de-solder the rtc and solder a dip slot then replace with a new rtc (dont break your motherboard while doing this like I did to mine)
2. Hope and locate a external battery plug if your board has one.
3. Modify your current rtc, this means cutting it open and attaching a button cell to the connections inside - there is a bit of info with pictures online for this

Around the time of early 486 8x would of been the fastest cd drive, there is a dos utility that can slow faster drives down mostly to make less noise, could use this on a faster drive if you really want to feel you have a certain speed under the hood
utility is called cd be quiet - cdbq

treeman wrote:

win 3.11 was only dual boot, boot to dos then manually launch win, unless you set it up in autoexec.bat to do auto […]
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win 3.11 was only dual boot, boot to dos then manually launch win, unless you set it up in autoexec.bat to do auto

If you use a large cf card you will have to partition and format it to a smaller size. Fat is 2gb max and so is dos 6.22, dos 7 will read a 4gb partition.
It also depends on your bios/ide controller card how much it will see.
For example on my 486 the bios will see my whole 2gb cf card but my ide controller card will only see 502mb which results in alot of sector errors.

So first figure out what your bios/controller card will handle go with 502mb if you want to be safe, probably about right for that time.

Around the time of early 486 8x would of been the fastest cd drive, there is a dos utility that can slow faster drives down mostly to make less noise, could use this on a faster drive if you really want to feel you have a certain speed under the hood
utility is called cd be quiet - cdbq

Yes, LGR has a good video on how to setup a CF card in DOS on and old 486.
https://youtu.be/VWfTgga7rmA?t=252

You can use the "clearhdd" utility to setup the CF card.

Here are the Graphics cards I have to choose from.
Which should I choose ?
I don't even know the specs of them.

The Oak Tech graphics cards was my original card from my first computer. ( 486dx-33 ).

These are the Sound Cards I have.
Which ones should I use ?
Some also have a Yamaha OPL chip.

To start with I would just go with the AWE64. Easy to setup and will support pretty much anything from Adlib, Sound blaster, AWE.
Once the PC has been running for a while you can try adding true OPL chip and seeing if the adlib games sound better.

CD-ROM, slow and steady is the answer.
A 486 cant keep up with faster drives which casues the drive to constantly spin up and down
a slower drive will just keep spinning at a slow steady rate.
But I wouldn't wast money trying to find say a 12x I cant remember the name but their is a utility that can set a faster drive to slower rate

Try to use 8 MB RAM (8x 1 MB). (30 pin, 70 ns, FPM). I don't think there are 30 pin EDO SIMMs.
A DX2/66 should be fine.
Take the ET4000 graphics card.

There were no 30 pin EDO modules and 72 pin ones would not work.
You can install either 4 or 8 modules, there are two memory banks there.
The tseng is the fastest card and the realtek the slowest by far. The tseng is really the only good card there.
About the cpu the dx2-66 is faster than the dx2-50 as expected.

Okay,
Graphics - ET4000 graphics card.
Memory - EDO 8-16mb.
CPU - Intel 486dx-50
CDROM - 4x - 12x

Audio ? Take a look at that Crystal card it has build in Yamaha OPL. I also have a Media Vision card with built in Yamaha OPL.

What about these controller cards ?
Which is bests ?

More cards

One more card.

dondiego wrote:

There were no 30 pin EDO modules and 72 pin ones would not work. You can install either 4 or 8 modules, there are two memory ba […]
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There were no 30 pin EDO modules and 72 pin ones would not work.
You can install either 4 or 8 modules, there are two memory banks there.
The tseng is the fastest card and the realtek the slowest by far. The tseng is really the only good card there.
About the cpu the dx2-66 is faster than the dx2-50 as expected.

I think this is not correct there is indeed fpm and edo in 30pin

check this post Q: EDO vs. FPM - how to tell which is which