Tetrium wrote:

Afaik most 486's seem to actually be quite easy to overclock, especially if you have a board that supports the "magic jumper", meaning it can halve the PCI bus compared to the FSB.
However, even though the 133Mhz chips (which are usually AMD 5x86's)

If you want good fpu performance, maybe a Pentium Overdrive wou8ld be a good idea?

I will look at board when I get home. It sounds like it will be challenge for my level of knowledge though! Maybe somebody here has experience of overclocking on this motherboard?

Actually I just read this about Pentium overdrives for 486 (see the bit in bold).

"OverDrive for 486 Systems: This Pentium OverDrive is specially modified to fit the 32-bit data bus of a 486 system. As you know a Pentium normally uses a 64-bit data bus, but this is not consistent with a 486 motherboard's design. Therefore, this OverDrive is modified to use an external 32 bit bus. This reduces performance compared to a real Pentium, which is one reason why these chips score below what would be expected for a real Pentium of the same speed. Interestingly, this chip has a 32 KB primary cache, double the size of regular Pentiums. Presumably this was done to help mitigate the effects of this chip running on a 32-bit motherboard. (It's still slow, and in fact, slower than the top-end 486 and 5x86 chips that run in the same motherboards and cost much less).
The Pentium OverDrive for 486s is available in two speeds: 63 MHz for 25 MHz bus systems and 83 MHz for 33 MHz systems. They obviously use a clock multiplier of 2.5. These chips are designed to work in a 5 volt system, and go into a Socket 2 or Socket 3 (the socket 3 must be set on 5 volts)."

This would indicate that a top end 486 chip would outperform these anyway?

rick12373 wrote:

Actually I just read this about Pentium overdrives for 486 (see the bit in bold). […]
Show full quote

Actually I just read this about Pentium overdrives for 486 (see the bit in bold).

"OverDrive for 486 Systems: This Pentium OverDrive is specially modified to fit the 32-bit data bus of a 486 system. As you know a Pentium normally uses a 64-bit data bus, but this is not consistent with a 486 motherboard's design. Therefore, this OverDrive is modified to use an external 32 bit bus. This reduces performance compared to a real Pentium, which is one reason why these chips score below what would be expected for a real Pentium of the same speed. Interestingly, this chip has a 32 KB primary cache, double the size of regular Pentiums. Presumably this was done to help mitigate the effects of this chip running on a 32-bit motherboard. (It's still slow, and in fact, slower than the top-end 486 and 5x86 chips that run in the same motherboards and cost much less).
The Pentium OverDrive for 486s is available in two speeds: 63 MHz for 25 MHz bus systems and 83 MHz for 33 MHz systems. They obviously use a clock multiplier of 2.5. These chips are designed to work in a 5 volt system, and go into a Socket 2 or Socket 3 (the socket 3 must be set on 5 volts)."

This would indicate that a top end 486 chip would outperform these anyway?

Only when it comes to integer performance. The Pentium's float performance is a lot better then any other 486, perhaps even the best one.
And when it comes to voodoo, you want lots of FPU powa!!1 😉

No a 486 Overdrive is not worth it.
You can get a Pentium 1 machine reeeeally cheap these days, and since you already have a Pentium 2 machine, just get a Voodoo 1 and install it there. The 486 is just not up to it and fitting a Voodoo 1, let alone a Voodoo 2, would create a huge bottleneck. It is kinda interesting to see how it fares, but not for everyday use. Is there any reason to use a 486 instead of a Pentium 1 anyway?

Tetrium wrote:

rick12373 wrote:

Actually I just read this about Pentium overdrives for 486 (see the bit in bold). […]
Show full quote

Actually I just read this about Pentium overdrives for 486 (see the bit in bold).

"OverDrive for 486 Systems: This Pentium OverDrive is specially modified to fit the 32-bit data bus of a 486 system. As you know a Pentium normally uses a 64-bit data bus, but this is not consistent with a 486 motherboard's design. Therefore, this OverDrive is modified to use an external 32 bit bus. This reduces performance compared to a real Pentium, which is one reason why these chips score below what would be expected for a real Pentium of the same speed. Interestingly, this chip has a 32 KB primary cache, double the size of regular Pentiums. Presumably this was done to help mitigate the effects of this chip running on a 32-bit motherboard. (It's still slow, and in fact, slower than the top-end 486 and 5x86 chips that run in the same motherboards and cost much less).
The Pentium OverDrive for 486s is available in two speeds: 63 MHz for 25 MHz bus systems and 83 MHz for 33 MHz systems. They obviously use a clock multiplier of 2.5. These chips are designed to work in a 5 volt system, and go into a Socket 2 or Socket 3 (the socket 3 must be set on 5 volts)."

This would indicate that a top end 486 chip would outperform these anyway?

Only when it comes to integer performance. The Pentium's float performance is a lot better then any other 486, perhaps even the best one.

I see. Thanks.

rick12373 wrote:

I was wondering is my motherboard (ASUS 486 Socket 3 Motherboard PVI-486SP3) capable of overclocking?

Yes. It is possible to raise the bus clock from 33 to 40 MHz, which gives a considerable performance boost. It would overclock your AMD DX4-100 to 120 MHz, which is usually no problem with these CPUs. On the other hand, you could run into problems with some PCI cards, because the PCI bus would run at 40 MHz as well, which is higher than the specification.

rick12373 wrote:

I am not in front of the 486 right now. If it is I assume it is all done through jumper settings?

Yes. The jumper settings are printed onto the board.

F2bnp wrote:

No a 486 Overdrive is not worth it.
You can get a Pentium 1 machine reeeeally cheap these days, and since you already have a Pentium 2 machine, just get a Voodoo 1 and install it there. The 486 is just not up to it and fitting a Voodoo 1, let alone a Voodoo 2, would create a huge bottleneck. It is kinda interesting to see how it fares, but not for everyday use. Is there any reason to use a 486 instead of a Pentium 1 anyway?

The reason I am running a 486 DX4100 is mostly for nostalgia reasons (it was the favorite DOS setup I ever owned). I wish I could remember the specs of the one I owned back then had.

F2bnp wrote:

No a 486 Overdrive is not worth it.
You can get a Pentium 1 machine reeeeally cheap these days, and since you already have a Pentium 2 machine, just get a Voodoo 1 and install it there. The 486 is just not up to it and fitting a Voodoo 1, let alone a Voodoo 2, would create a huge bottleneck. It is kinda interesting to see how it fares, but not for everyday use. Is there any reason to use a 486 instead of a Pentium 1 anyway?

You're right, and it was mentioned before. But as the OP wanted a 486 and a voodoo, his best bet would be a cpu that can do loads of floating point operations a second.

And for the record, the 486 Overdrive is a different chip from the Pentium Overdrive.
The 486 Overdrive is basically a standard 486 while the Pentium Overdrive (commonly known as the PODP5V83) is actually the same size as the Pentium for Socket 7! But with a pinout for Socket 3.

And a reason for running a 486 instead of a Pentium? Not really, except 486 is a more adventurous territory to trek through. Compared to 486, Pentium land is quite boring 😜

But then again, pentium does have it's own nicelies, like: Winchip, Cyrix, K5, K6, K6-2 and it's mobiles...AT and ATX, AGP and lots more!

Just found an old Dell motherboard (e139761) with this CPU in it:

http://www.cpu-world.com/sspec/SL/SL26J.html

I think I will put together a new system based upon this.

rick12373 wrote:

Just found an old Dell motherboard (e139761) with this CPU in it:

http://www.cpu-world.com/sspec/SL/SL26J.html

I think I will put together a new system based upon this.

It would definately be much better suited for that voodoo!
In any 486 (be it POD, 5x86 or whatsnot) the voodoo will be starving for data all the time.

Anybody know anything about this board? It is a Dell and it has E139761 written on it. I have been trying to find a manual for it.

Pic?

Here you are...

It seems there were a lot of Dell motherboards with E139761 on them. This has a Pentium 200 in it and on-board sound (vibra 16C CT2505-tdq2). It has 4 PCI slots and 3 ISA slots. The chips say PCI set SB82437VX L6514671 and PCI set SB82371SB L6522968 (if that helps).

I hope I can disable the on-board sound so that I can put a Sound Blaster in there.

I believe that your board is actually made by intel, and is a variation of this one : http://stason.org/TULARC/pc/motherboards/I/IN … um-TE430VX.html

Markk wrote:

I believe that your board is actually made by intel, and is a variation of this one : http://stason.org/TULARC/pc/motherboards/I/IN … um-TE430VX.html

I think you may be right. This board does not have on-board video though (which is good). I hope I can disable the on-board sound though.

I think this might be a little hard. A friend of mine had a similar soyo board(atx with integrated vibra 16) and it wasn't possible. That board also had a regular waveblaster connector, whereas yours has I think the "goldfinch" connector which is only for the ct1920 add-on card, that "transforms" it to an AWE 32.

Markk wrote:

I think this might be a little hard. A friend of mine had a similar soyo board(atx with integrated vibra 16) and it wasn't possible. That board also had a regular waveblaster connector, whereas yours has I think the "goldfinch" connector which is only for the ct1920 add-on card, that "transforms" it to an AWE 32.

Well that's annoying. It might be a good board if it wasn't for that.

Well, the integrated card is a sound blaster. If you want to have just a regular sb16, it's going to be fine. If you want to add some better card for midi playback, it would be interesting to find a bugless and trouble-free sb-compatible with waveblaster connector.Then you could use that for midi, and have all the digital sounds played by the vibra16.

Markk wrote:

Well, the integrated card is a sound blaster. If you want to have just a regular sb16, it's going to be fine. If you want to add some better card for midi playback, it would be interesting to find a bugless and trouble-free sb-compatible with waveblaster connector.Then you could use that for midi, and have all the digital sounds played by the vibra16.

So I could get SB16 functionality in DOS? If that is the case then I am happy with that. Which drivers would I use for the sound in DOS?