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So I bought a PCI 486 board...

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smeezekitty

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So my addiction continues.
I just bought an Acer AP43 motherboard.
That would be my first PCI based 486 motherboard.

I want to build yet another 486 system but I have lots of questions as always. (sorry)

First of all is RAM. It takes up to 128MB of 72 pin RAM.
What is the difference between EDO and FPM RAM? Which one does it take?

I want to install atleast 64 MB of RAM because I want to run more modern OSes like Windows 98, NT and Linux with GUI

It comes with 256 KB of cache and handles up to 512. What setup of cache would handle all 64+ MB?

Also it has four slots so would 1x64, 2x32 or 4x16 be best?

Another confusion is PCI slots. From what I understand
old slots used to be 5v and new ones are 3.3v. Furthermore some have the notch reversed.

How do I know what cards will work without malfunctioning/blowing up?
Can the differences between new PCI and old PCI be explained in general?
Any ideas on a PCI graphics card to use?

What kind of CPU coolers are used on 486 CPUs?

I know that is a lot of questions but this would be my first vintage build from scratch
 
RAM:
2x32 or 4x16MB
I'd go with FPM - just because it's of the right era and there is less likely to be complications, but EDO is the fastest if supported. Also if you're choosing between 60ns and 70ns - go for the lower number.

Here's a link to your motherboard (jumpers etc) http://stason.org/TULARC/pc/motherboards/A/ACER-INC-486-AP43.html#.Uyikn4Vj9aQ

PCI:
3.3 and 5V is supplied on different pins, but your 486 may not provide 3.3V - so some cards may not work but nothing will blow up.
Quick article I found here: http://www.soundonsound.com/sos/dec04/articles/pcnotes.htm

Heatsink:
486's generally don't need them, and if they do it usually says "HEATSINK REQ'D" on top - something like a DX2/80 or DX4/100 I'd be inclined to install one even if it didn't have that written on it - usually (the ones I've seen) they're just generic ones stuck on with a thermal transfer glue and a little fan on top doesn't hurt too (you can still buy these generic ones for cheap - because they have lots of uses).

Cache and video card, I'd have no idea. Hope that helps a little.
 
SpidersWeb said:
RAM:
2x32 or 4x16MB
I'd go with FPM - just because it's of the right era and there is less likely to be complications, but EDO is the fastest if supported. Also if you're choosing between 60ns and 70ns - go for the lower number.
Click to expand...
Ok thanks. It looks like it is pretty flexible with RAM configurations but I will stick with FPM
Here's a link to your motherboard (jumpers etc) http://stason.org/TULARC/pc/motherboards/A/ACER-INC-486-AP43.html#.Uyikn4Vj9aQ
Click to expand...
Yeah I saw that. One of the best mobo references around
PCI:
3.3 and 5V is supplied on different pins, but your 486 may not provide 3.3V - so some cards may not work but nothing will blow up.
Quick article I found here: http://www.soundonsound.com/sos/dec04/articles/pcnotes.htm
Click to expand...
Maybe so for the power voltage. But what about the signaling voltage?
Heatsink:
486's generally don't need them, and if they do it usually says "HEATSINK REQ'D" on top - something like a DX2/80 or DX4/100 I'd be inclined to install one even if it didn't have that written on it - usually (the ones I've seen) they're just generic ones stuck on with a thermal transfer glue and a little fan on top doesn't hurt too (you can still buy these generic ones for cheap - because they have lots of uses).
Click to expand...
I am planning to run a DX4/100 in it eventually so I would probably want some cooling.

Even my 486DX/33 has a heatsink and it gets pretty warm.

Thanks for the information
 
I always use a heatsink with fan on my 486s.

I've got several NIB NOS 486 heatsink/fan combos as well as some 486 DX2-66 and DX4-100 cpus if you're interested.
 
smeezekitty said:
Maybe so for the power voltage. But what about the signaling voltage?
Click to expand...
My expectations/understanding was if it fits in the slot, it should be 5V tolerant.

Googling around the place, found this on wikipedia:
"The PCI SIG strongly encourages 3.3 V PCI signaling,[13] requiring support for it since standard revision 2.3,[15] but most PC motherboards use the 5 V variant. Thus, while many currently available PCI cards support both, and have two key notches to indicate that, there are still a large number of 5 V-only cards on the market."

(shows that despite the standard being updated, in practice, 5V signaling was common anyway).
 
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SpidersWeb said:
My expectations/understanding was if it fits in the slot, it should be 5V tolerant.

Googling around the place, found this on wikipedia:
"The PCI SIG strongly encourages 3.3 V PCI signaling,[13] requiring support for it since standard revision 2.3,[15] but most PC motherboards use the 5 V variant. Thus, while many currently available PCI cards support both, and have two key notches to indicate that, there are still a large number of 5 V-only cards on the market."

(shows that despite the standard being updated, in practice, 5V signaling was common anyway).
Click to expand...

Well its all pretty confusing but I guess it wouldn't hurt to try a PCI card then. I wonder if the board could be modified to provide 3.3v as well
 
EDO came along in the Pentium era...I don't think even the early Pentiums supported EDO. It is possible a 486 board could use EDO, but I would be surprised if it would work. FPM = Fast Page Mode, EDO = Extended Data Out.

As for the amount of RAM...when Windows 98 and NT4 were common, 64Mb was a lot of RAM! 486's were also getting to be old technology by that time... 16-32Mb of RAM would likely serve you well with a 486 system. Also keep in mind that with a 486 and 72-pin SIMMs, you can add them in one at a time, they don't need to be in pairs, so you can easily expand as you see fit. I would also guess that 16Mb chips are going to be cheaper and easier to find than 32's...though either are on the large (and likely rare) side for FPM chips...

Video card...ATI, Cirrus Logic, S3...they were all fine in my experience.

In my recollections, 50-66MHz was the point at which most machines started using CPU fans. I don't think I ever saw a 486/33 with a fan...and can only think of seeing maybe one DX2/66 without.

Wesley
 
IIRC, Fast Page Mode allows the memory controller to pick a row address, leave it latched on the RAM, and then just change the column address to get to any other addresses within the row.

Extended Data Out leaves the last addressed data valid on the data bus (hence the name) while the memory controller changes to the next address.

As mentioned you should probably use FPM as it's the older style RAM and the memory controller will support it for sure. If it's an oddball motherboard that came available in the mid-90's it might take EDO.
 
I'd say they're perfect. 60ns, FPM, etc. I'd grab a couple for 5 bucks each.

But one thing I spotted is that it says "parity" yet the photo is missing the 9th chip. It's probably just a stock photo, but thought I'd mention it.
 
SpidersWeb said:
I'd say they're perfect. 60ns, FPM, etc. I'd grab a couple for 5 bucks each.

But one thing I spotted is that it says "parity" yet the photo is missing the 9th chip. It's probably just a stock photo, but thought I'd mention it.
Click to expand...
I saw the same thing hence the hesitance. Its one of the few that is even marked parity though
 
Generally PC needs parity, old mac does not. I think you needed to have a Pentium ERA machine to be able to use EDO, otherwise it looks like FPM to an older chipset (if it could deal with the chip density).
 
Unknown_K said:
Generally PC needs parity, old mac does not. I think you needed to have a Pentium ERA machine to be able to use EDO, otherwise it looks like FPM to an older chipset (if it could deal with the chip density).
Click to expand...

Hmm... really? I don't recall too many of the clone motherboards I worked on back in the day requiring it, but I may not be remembering right. Certainly not with the the newer machines Pentium era and better.
 
smeezekitty said:
What do you think the chances of getting a PCI USB card to work?
Click to expand...

If you're running an OS that support USB you should be okay. You will need to check the USB PCI and see what drivers are available. There may be some solutions kicking around for USB/DOS but I haven't had the gumption to get into yet. As far as the case, if you can cram it in there it ought to work. A possible bottleneck would be the type of P/S and the location of the on/off switch on your case. Of course you can always get creative there. Good luck with your project
 
smeezekitty said:
And another thing is the case. Will it fit in an ATX case or do I have to scrounge an AT case?
Click to expand...
When you say 'fit' do you mean dimensions or connections? Even if the dimensions are OK the connections are not. AFAIK, an ATX case has (among other design inconsistancies) a PSU connector that does not match an AT connector on the motherboard.
 
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