Taking a 486 SX-25 and the FIC 486-VC-HD to the Max!

[@adriansdigitalbasement]

A new vswitchvideo? I see, I watch ASAP! Excellent video, that truly is an under appreciated little beast of a CPU. To think back then someone would just need to spend a few 10s of dollars on some crystals and they might be able to attain that 100% OC.

[@Paar86]

People were probably not knowledgeable enough back in the day, especially without the Internet. I wonder how many actually did overclock their system.

[@BrassicGamer]

@@Paar86 I had a 486DX4/100 that I overclocked to 120MHz just by increasing the bus speed. The key difference here is that knowledge about timings and such wasn't as widespread back then and I, for one, was terrified of breaking either my CPU or the motherboard that had cost so much money. Not so much of an obstacle these days when you have a stack of CPUs and motherboards at one's disposal.

[@adriansdigitalbasement]

@@Paar86 we had BBSes and magazines and you'd be surprised what kinds of info was shared back then. Overclocking has been going on since the original PC and XT and before that.

[@vswitchzero]

Haha thanks so much, Adrian! 😁👍

[@RetroTinkerer]

@@BrassicGamer yeah the cold sweat when you tried a higher multiplier or the next FSB speed available on that sea of jumpers and the system failed to boot only to realize you didn't read correctly the manual, that was some intense stuff!

[@MonochromeWench]

I saw the thumbnail and I was ready to say we know so much more now about how to overclock things then back in the 90s but no modern wizardry needed here, it all just worked as is.

[@T3hBeowulf]

"Rise from your grave!" - Altered Beast This gives me a bit of hope. My childhood PC in 1992 was a 486DX-50 and I still have it today. The VLB slot is useless at that speed but I'm hoping I can get a SCSI card working as it's jumped for "33Mhz and higher" Impressive overclock and results!

[@tiemanowo]

Ahh. 486 SX-25. I have some good memories about this exact model. I was working as a teenager during one summer to buy my first PC. But unfortunetly prices has changed and i was able to buy only 386 DX-40. At first I was little bit disapointed but those bad feelings has passed away. It was my first PC afterall and at the and I was happy.

[@fungo6631]

You should had built one yourself, by buying a pre-built you sometimes paid Pentium custom build prices for 486 systems.

[@mal2ksc]

You probably were only losing out on a ~20-25% performance increase. The fastest 386 and the slowest 486 behave pretty similarly, especially the 486sx which lacked the FPU.

[@fungo6631]

@@mal2ksc Clock by clock a 486 is generally about twice as fast as a 386. In Doom even more than that.

[@orbatos]

My 386 with a 387 made getting a 486 pointless until the later models.

[@fungo6631]

@@orbatos Yeah, no. The 486 has around 2x the performance per clock. Even 486DX 25 will shit on the fastest 386.

[@derre98]

One sound chip that works well with 20 MHz ISA CLK is standalone OPL3 (YMF262). Just tested with homemade PCB myself. Everything 0 WS on 40 MHz 386DX and I even have 0/0 I/O recovery.

[@awilliams1701]

There are a couple of channels I'm subbed to that rarely post videos, but they are insta click subs for when they do post. I can't think if it's more than 2, but yours is one of them. The other is CSI Starbase. Both posted videos today! How exciting! lol

[@SobieRobie]

Most people back in the days were too scared to overclock their precious 486 😂

[@noanyobiseniss7462]

Not sure if it was your channel but I commented to someone doing doom trials that I used to put the demo on loop under win3.1+3.11wfw back in the day overnight as a burn in and stability test before delivering a system. If you can do that without a blue screen then you know what your doing and your real mode drivers are rock solid.

[@LotoTheHero]

That 2X Overclock is awesome!

[@FOIL_FRESH]

Insane performance gains

[@SockyNoob]

If only it worked like this for modern systems. Imagine a 100% in performance.

[@Somelucky]

The 486SX/25 with an upgrade socket was my first PC at the end of 1992. I remember saving up enough money by the end of the following summer to get a DX2/66 and double the RAM.

[@Vile-Flesh]

I wish I had known how to do that back in the early '90s, I would have gotten a DX4 overdrive 75mhz. Our family 486 was a Biostar with the soldered on 486sx25 with an upgrade socket. We weren't allowed to tamper with the computer and we were afraid of any wrath incurred by fucking something up but we suffered with that 486sx25 till 1997 when we finally got the Pentium 133.

[@Somelucky]

@@Vile-Flesh the DX4/100 essentially required an early Pentium board. That was my next PC in 1996.

[@djpirtu2]

I have overclocked 386 and 486 machines a lot and one reason why the memory dont need wait states @50MHz because wait states are set on cache. Every memory access goes through cache. If you put 15ns or 12ns cache which work at 0WS @50MHz then it's maybe necessary to put WS on memory 😅

[@spladam3845]

Great video again, back in the day, this would have been a brag worthy upgrade. In my little circle back then, increasing the clocks of the ISA bus was a must, but what you did here would have blown us away.

[@drkamilz]

I remember the same issue back in the day. My 486DX machine with overclocked ISA bus to 16MHz worked fine until the SB16 Vibra card was installed.

[@jrherita]

I never saw a 486SX packaged in that way before; I always remember seeing 386SX’s in this packaging and thought it looked advanced for the time. This looks like a pretty good budget choice for 1992! Subbed. (My first OC was a 486DX-25 laying around that I finally put in a ‘33 MHz board’ in 1992 or so.. eventually a Digikey oscillator assortment got that combo to 48 MHz stably :) ).

[@tabeschektabeschek1852]

I had a 486sx25 overclocked at 44MHz. Good times.

[@BrassicGamer]

Kudos for this! I think they key thing here is that I wouldn't even have bothered to try and push the system to 50MHz, and I doubt many others would as it's a bit, well, illogical. 🤣 Thrilled at this result, particularly the ISA tweak. I don't think I've ever had a board that was as tweakable as the ones you find.

[@Phantomwiz1985]

The old 486. Was a great time to be alive. Another top quality video vswitch. Can’t remember having a sx. But did have a dx. Played duke nukem and doom for ages. Love it. Will wait eagerly for the next one. Cheers

[@paulmichaelfreedman8334]

I overclocked my P100 to 150 in 1999. Pure FSB overclock. Made it very fast and worked like a charm, no issues. Ran Quake III arena with a voodoo1 @ 40fps.

[@RetroInside94]

Woow what a smash! You literally doubled the performance and the clocks! I love this thing! Very very nice video! Oh and yes i am the distibuitor of the PSU 😂😂 (see the sticker)

[@vswitchzero]

Thanks very much for watching! Glad you enjoyed the video :)

[@idahofur]

I loved my 486sx-25 processor mb with 8mb of ram. Ran great for dos and windows 3.1

[@TechAmbr]

POWER UP!

[@lemagreengreen]

John Romero said "the SX stands for sucks!" about the 486SX, he wasn't that wrong in the context of Doom but if we were brave enough to overclock like this back in those days maybe it wouldn't have sucked so much at Doom.

[@Zerbey]

Gosh I wish I'd known you could just swap out the crystal back in the early 90s when I had my 486SLC-33, I've no idea if it would have overclocked but I'd have definitely tried!

[@TheCarlos206]

THX!

[@Ale.K7]

Amazing! :D

[@MissNorington]

Awesome video!

[@Alcochaser]

Most ISA cards were designed for 12mhz. This is because a lot of 286-12 boards didn’t use a divider on the bus. Card makers knew this and this designed their cards for 12mhz.

[@itstheweirdguy]

Your videos are very logical, polite, under control, very well thought out....where's the chaos? The adventure? The fantasy? You're just missing a little pizzaz.

[@Phil-D83]

Cool to mess with. That powerleap 5x86 133 seems to be the apex of 486 performance

[@Vlad-1986]

Cool! Maybe with this setup you can make a 486-25SX actually less annoying to play Civ2! It might even pull Sim Tower for a bit longer.

[@fra4455]

Great video

[@toseltreps1101]

good one

[@matthewday7565]

If you could get a set of -15 cache, maybe even faster - and does it benefit from a dual bank cache?

[@ErrantMasa]

yeah; the next steps would be 60ns RAM sticks and 15ns cache, to whatever maximums the mobo and chipset can support

[@xenon2Merchant]

Very cool (I guess :D ), I wonder what are the temps of the CPU per each freq.

[@christ2290]

It'd be cool to see your overclocked SX @ 50MHz vs an actual SX2-50 to see how much the bus speed impacts benchmark performance.

[@pvc988]

I wonder if VLB (or even PCI) adapter for CPU socket could be made. Something like you wold see in an Amiga.

[@O.Shawabkeh]

Doom worked fine on 486/SX, 16MB FP ram, integrated Cirrus Logic. I don't know from where you guys get those slow numbers.

[@paulmichaelfreedman8334]

Pretty sure I had this motherboard in my PC, somewhere around 1994/1995. That said, my PC has seen MANY mobo's over the years.

[@jrherita]

Just curious - how much power (watts) does this 486 set up use without monitor?

[@pr0fanator]

Wish you more subs ;) Who needs fast Doom with OC on 100% level :D

[@vswitchzero]

Thanks for watching! 🙂👍

[@dennisp.2147]

Your CPU is actually dated 14th week of 1993.

[@YarisTex]

A UMC CPU would help a lot here, with it’s increased efficiency you could probably settle for a lower ISA speed and still be slightly faster…but yeah it wasn’t available in 1992

[@kokodin5895]

but how fast can it go really? when you halt the onboard cpu and stuck some dx4 into the 487 socket?

[@TrolleyMC]

that wouldn't work, the DX4 would have to be initialized and to have the registers from the SX to the DX4

[@TheFlagshipLab]

That's an OC.

[@TheFlagshipLab]

Would low temps help?

[@BandanazX]

And I thought I was a badass overclocking my Pentium60 to 66MHz. Oh well at least I got a real 66MHz Pentium when I took it in for the FDIV bug CPU replacement.

[@Steampunk_Star_Raisin]

#verynice

[@vabello]

I was going to say, that Doom performance seems atrocious from what I remember on my 486SX 25. I think I had a VESA video card though, but I can't recall. I used to play Doom on 25MHz 386 machines (I can't recall if they were SX or DX). This was in my computer lab in high school. We shrunk the screen down much smaller, but it was perfectly playable. We did multiple simultaneous 4 player Doom matches over the Novell network.

[@fungo6631]

12 FPS in Doom at 40 MHz is kinda slow when a 486DX2 66 can run Doom at almost full speed. In the Thandor Doom benchmarks the SX25 gets 14 FPS at 25 MHz, although it is on a PCI system.

[@throwaway6478]

Most of the issue would be the ISA VGA. I had the misfortune of having to run a 486DX2-50 on an ISA video card for a few weeks after my off-brand Tseng Labs ET4000/W32p committed hari-kari, and I still have the odd nightmare about its 386-like performance.

[@jaybird57]

Ok. Now stick a DX in there and lets see how much it helps doom.

[@throwaway6478]

Not even slightly. Reasonably well-known fact: Doom specifically used integer math so it didn't need a copro. Quake was the first ID game to use x87.

[@ErrantMasa]

@@throwaway6478 are there any bits of vanilla DooM code that would benefit from being converted to use floating-point math? that'd be an interesting direction to take both it and Wolfenstein 3D

[@PROSTO4Tabal]

Dommaholic lol

[@WoWSBrewsandBoats]

6th!

[@Thelemorf]

13:35? You have some nerve to not make the video 2s longer! /jk

[@glenncaughey5044]

You have the mach32 isa. Wish I had that one. I only have the pci mach32. 🤌😅