A fast 486 that isn’t (a 486)

I've been putting this thing together over the last few months as the mood strikes me - a nice way to do things compared to my usual rabid push to get things done ASAP. It came about because I spotted an AT flip top case locally and I've been on the lookout for a replacement for years after an attempt to paint my last one ended in tears.

Hey, that rhymes.

This one is just another classic early 90’s clone. Cheaply made, functional, and sent to landfill in droves when the WWW took off and people upgraded to Pentiums. They’re getting hard to find around here these days and the condition of this one was a little rough, so it took some patient cleaning-up to get into a useable state. The drive bay covers - which I suspect aren't original - were the only yellowed plastic but came up OK with some sanding / respraying with clear semi-gloss.

The PSU was a challenge because where I'd usually just toss the old one and install a new StarTech AT unit, this case is a side-switcher (one of the reasons I bought it)(nostalgia), so I ended up gutting the original unit and switching in the contents of a StarTech unit instead. That worked well in the end but was fiddly, with some removal of components / soldering required.

The motherboard is the mighty ASUS VLI-486SV2GX4 rev. 2.1, which is almost too easy to work with to be considered a real 486 board. Still lots of jumpers, but they're clearly layed out and the board works like a charm with all 486, 586, and POD CPUs I've thrown at it over the years. For this machine I went with a POD83 I've had sitting around for a while - I already have an SX33 machine so I was looking for something a little more exotic here. The CPU fan was noisy which was dissapointing considering it's new-old-stock, but opening it up and giving it a lube sorted it out.

The VGA card is another NOS item I've had sitting around - it's a no-name S3-805 based VLB number which I upgraded to 2MB of RAM. I've been really impressed with this thing so far - VESA 1.2 out of the box (3.0 with SDD) and the image quality is beautiful in VGA and low-res SVGA. I need to copy the driver off the 5.25 floppy and max out the resolution in Windows 3.11 to see how the image quality holds up, but this is a DOS gaming machine so it's perfect in that context.

For sound I've dropped in an AWE64 Value that I've been avoiding for years for no reason other than it's just too easy. The AWE64 sounds amazing I think, the drivers / software are great, and CQM sounds really good with some reverb and chorus added. The AWE side of things is OK - not a patch on a half decent GM device in most titles but easily holds its own when it's used properly; X-Wing is a good example of how good it can sound. And just in case I'm in the mood for loading up some sound fonts in Windows 3.11 (very unlikely!) I've snuck in a 32MB memory expansion (28MB useable) via the amazing SimmConn, which is out of production now I think but used to be available for 20 bucks or so.

I'm using a period correct HDD for the boring stuff like OS, etc, but I always like a IDE->CF adapter for games, machine specific drivers, etc so that I can easily transfer files and back it all up. I usually use an externally accessible unit but I didn't have one handy, and given it's so easy to flip the lid on this thing I thought the internal option was just fine. There's a 50% chance that these things don't work in my experience but I got lucky with this one.

Performance wise it's pretty impressive for a "486". DOOM runs smoothly and Duke3D is quite playable, though you can notice some slowdown even in VGA mode. C&C is OK-ish but Warcraft II doesn't feel playable to me - I played all of these games and more on my trusty DX2 66 back in the day but it's hard to un-see everything that's happened since the mid 90's. Pixelated graphics I can do, low frame rates are a bridge too far.

 

Looks very, very clean and nice. Does that video card have vIrge metal 3d acceleration.?
Resolving the psu is half the battle : nice work there there!

Callan

 

Very nice and tidy machine ! Your cable managemnt is very tidy too, my old PC's look like a rat king.

The VLI-486SV2G is an amazing board. I've been through several 486 boards over the years and this is the most reliable and flexible by far.

 

No this 805 chipset came well before the ViRGE and 3D - the bios is from 94 but I suspect this basic card would have been around since 91 or 92. The performance is on par with the go-to cards of the day but certainly not spectacular. Very compatible though.

Thanks yes I surprised myself with the cable work - I have the CD-ROM as a slave on the IDE HDD which helps with keeping it simple. From memory this isn't the thing to do for IO performance but most things will be loaded off the second master, which is the CF, so should be all good.

BTW my VLI-486SV2G is sporting the latest BIOS, which you burned for me years ago

 

Really nice build. The PSU came up tidy, wouldn't know from the photos you swapped out the internals.

How's the POD compare to a DX4 or even a Cyrix 586?

 

Nice, where did you source the StarTech AT PSU, I've never been able to find them locally?

 

Awesome work there mate

 

Yeah not sure to be honest, I plan on doing some benchmarks one day but my impression is that the POD is about on par with a 5x85 @ 133MHz, but I'm also under the impression that the POD has some compatibility issues. I'd also like to see if I can get WT cache going with the POD - I think I've managed that before with this board but I've forgotten the details.

I buy them in the U.S and Shipito them over - this has gotten rather expensive (~80AUD all up) but I think it's worth it to have a newly made PSU; one less thing to worry about.

 

I did some rough testing on this a while ago and found I got similar performance in Doom with a POD-83 and a 486DX4-100.

Of course, with Quake the POD stomps all over any other Socket 3 CPU.

 

Quake would be fun to try - I have a Voodoo1 sitting here but of course that ain't gonna help with my VLB motherboard. I do wonder how the POD and the Voodoo would go against Quake tho, a project for another day.

 

What is the memory simm on the sound card for?

 

It's a memory expansion for loading sound fonts in to, same idea as on the AWE32's but Creative got greedy with the AWE64 and whipped up a proprietary memory module that of course they sold for muchas $$$. They're pretty rare as a result and go for hundreds of dollars these days. What I have on there is a 'SimmConn', which is a third party device created by some clever Chinese dude. He stopped making them a couple of years ago but another guy is making them now.

 

Interesting. I have an old full length ISA sound card that has some 30pin simms on it. I suppose they are for the same thing.

 

I reckon I've a Voodoo card in a box somewhere...

 

Yep that'd be it, but yours will probably take 2 sticks of 30 pin RAM. Sound fonts are a lot more useful in Windows95 and up because from what I can see, there's no way of emulating an MPU401 in Windows 3.11 for use with DOS games (i.e so you can use their general midi option for music). And of course playing DOS games via Win 3x isn't much fun anyway. So all I can do is load fonts and play MIDI files.

Still pretty fun though

 

It's funny that the SimmConn was someone's uni holiday project:
https://www.vogons.org/viewtopic.ph...26d33f5be56d1eab341a5e16b101&start=20#p449303

Great story.

 

That's how a lot of things start. Linux was written by a guy on school break who couldn't afford UNIX.