The Forbidden and Forgotten UMC Green 486 CPU

[@erinwiebe7026]

In the mid 90's, I worked at a small, local (also Canadian) computer shop. It was one of my first jobs out of high school, and well before my IT career. I helped do all kinds of jobs there, including building made to order clone PC's. It was the mid 486 era, and we sold mostly Intel & AMD 486's. The shop owner showed up with a UMC 486 33 one day and at the time it was considered an oddity and it ended up sitting on the shelf for months before we finally decided to build a system around it. Seeing it run, I remember being rather surprised how well it benchmarked, and I wondered why we didn't see more of these CPU's making their way into new builds. It was the first and only UMC 486 CPU I ever encountered in person and your video brought back some fond memories of working at that little computer shop. Thanks!

[@vswitchzero]

Thanks very much and thanks for sharing! Always love to hear these kinds of stories from back in the 90s 👍

[@wowitsshit9734]

Ywnbaw

[@АндрейМилованов-у9у]

similar biography, but w/o GREEN CPU, few years before (begining of 90s) and in Russia

[@idahofur]

I remember the name but, I don't think the shop I worked for sold any.

[@dumiicris2694]

benchmarked back then? and i had 80 mhz amd so i so what it can do.. u have 12 16 33 .. 120 mhz what benchmarked? unbelievable.. first cpus 1 transistor and 1 resistor benchmarked? im speechless i can not beleve this sorry benchmarked because of faster ram or nice video card .. can not beleve this sorry .. a cpu that needs fast routines to make some graphics fast enough .. thank god i never seen benchmark back then..machine code everything if u want for things to move normal and yeah everything was a pain in the butt benchmarked!! :))))

[@the_beefy1986]

I love the use of Gameboy cart cases to store CPUs

[@tetsi0815]

I wonder where all the game cartridges are...

[@Sarge92]

@@tetsi0815 you can buy those brand new empty

[@bubu5908]

@@tetsi0815 In In the CPU packaging, of course.

[@rolux4853]

Yes! All my old CPUs are in a drawer with some dividers to separate them. Now I feel guilty that they slide around if you open and close that drawer a bit more quickly.

[@robertsmith2956]

I keep all mine in the box they came in when I bought them. Takes up a lot more room that way.

[@ugzz]

I remember "Zipping" Quake 1 onto about 15 floppies with max compression and a 1.4mb split. Backpacking that to a friends across town. All 15 floppies worked, recombining the zip worked. Fully extracted no problem.. We were SOOO geeked!.. Then we learned about FPUs.. No quake on a SX 486.. Such disappointment!

[@mirkoslavko3703]

There was a FPU Emulator, it worked well on my 486sx25@33 MHz.

[@John_Smith100]

Similar story splitting game demo downloads at school and taking them home across multiple floppies, then figuring out which split had failed CRC check. Got caught once hiding the download window behind a fake picture of a bare desktop.

[@ugzz]

​@@mirkoslavko3703 Whaaaa?? (mind blown!)

[@shelterbloodfallen8851]

Or Duke Nukem 3D, Transfer with Floppys. Ready to start Multiplay with Modem (No Internet, direct to a friend. Late afternoon).... oha Mainboard has a ... 8000er Serial RS232 Manage Chip. Makes the game unsyncing .... damm fast , i buyed a new Mainboard only for that game 🙂 Hahaha.... payback time!!!

[@jimbotron70]

​@@mirkoslavko3703No way working well for such a demanding game.

[@georgeh6856]

I am glad you said you are Canadian. When I saw that "NOT FOR U.S. SALE" label, I was about to call the CPU police.

[@vswitchzero]

😂

[@bleeedthebrakes]

At least UMC did learn from this and spawned into all other architectures that intel hadn't had their hands on. Mediatek, Novatek, JMicron, ITE, SiS, Faraday are all part of the UMC franchise.

[@SianaGearz]

Huh. SiS chipsets had the fastest memory controllers for a while, and were actually sort of robust and not too buggy.

[@tcpnetworks]

I used a UMC U5S in an embedded machine back in the mid-1990's. It was in charge of producing glass bottles at a production facility - in charge of 14 stampers and 2 furnaces, it kept everything working nicely.

[@geografiainfinitului]

That UMC logo looks something straight out of Robocop

[@glitchwrks]

Neat! I'd seen the UMC CPUs mentioned in motherboard jumper tables but never actually saw one in the wild.

[@udirt]

Same, I only remember that blue lighting ibm cpu as Enigma 3rd party cpu that was notably fast. Would have been cool to have had one of those!

[@Rouxenator]

I remember these, they were pretty common here in South Africa. My cousin has the SX40

[@Fusso]

Brazilian here. Had one those around 1995. It was pretty common. What I never saw was an original Intel one.

[@Zerbey]

Never heard of this before, but yeah I'm blown away by those benchmarks. Wish I'd known about these in the 1990s!

[@ville_syrjala]

I see no source for that 7 cycle integer division claim in wikipedia. Would be cool to actually test that. The "AGP" model of the Millennium II is in fact just a PCI device, and AGP runs at 66MHz, so it's possible that most Millennium II's can handle that frequency just fine, unless Matrox had to use special binned chips for the AGP cards.

[@udirt]

IIRC the et6100 etc were also quite overclock friendly

[@PiDsPagePrototypes]

Those things were so hard to get a hold of when brand new, then they were a pain to set up, and then suddenly they were everywhere, being tossed out with the Dell and HP business workstations they were standard fit in. The long sockets on their side were for the Video Graphics Overlay board that used software for doing Lower Thirds and the like in TV stations.

[@SianaGearz]

AGP will gracefully degrade to older PCI standards if need be, so a card doesn't need to support 66MHz.

[@HappyBeezerStudios]

@@SianaGearz A bit like with the Voodoo cards, which never made use of all the fancy AGP features.

[@intrinia]

And I thought I have seen every 486 manufactor. Great video!

[@vswitchzero]

Thanks very much! 🙂

[@HappyBeezerStudios]

Look at the Texas Instruments and ST Microelectronics 486

[@intrinia]

@@HappyBeezerStudios Have some of them laying around. ;-)

[@Telecasterland]

Am5x86 133 overclocked to 160 was the king of the hill of the 486 boards.

[@lynnjr457]

Even though they tended to overheat during long production usage. I worked for a company that decided instead of going to legitimate pentiums, we would deploy those overclock cpus. Until we figured out the overheating issue, we had months of machines hanging up randomly. Eventually we modified some 1U appliance fans with much higher RPMs that kept the CPUs cool.

[@Lalasoth]

@@lynnjr457 I had one of those but never had that issue. Was awesome for its time. When I would tell people about it I usually received nothing but disbelief.

[@briangoldberg4439]

Intel probably saw them as a real threat with those performance numbers. I mean, in productivity software, you wouldn't really need to upgrade to a Pentium until Windows 95 came out

[@effexon]

ah good old block dealerships to take competition by shady threats.

[@HappyBeezerStudios]

The 90s were so wild. Besides x86 with Intel, AMD, Cyrix, VIA, Texas Instruments, IBM themselves, UMC, ST, and a bunch more, there were also lots of other architectures still around. PowerPC, i960, Arm, 68k, SPARC Alpha, PA-RISC, AVR, SuperH, M32R

[@IronwingTechHaven]

This is so cool! I've never even heard of it. Awesome video. I especially loved the overclocking section.

[@benchang888]

Now UMC is making android cell phone CPUs competing with Qualcomm.

[@the_kombinator]

0:05 - I thought I was very much the only one storing 486/Pentium CPUs EXACTLY THAT WAY lol.

[@repatch43]

Is it crazy that I still care about benchmark results for 486 class CPUs? No, not crazy at all. Great video!

[@vswitchzero]

Haha thanks very much! 😁👍

[@josephalbrecht3735]

Thanks for a very informative and interesting video. I just picked up 486 VLB system with a PC Chips M912 v1.7 motherboard. I purchased UMC 486 Super40 that I will be using in this system. I never used one the CPUs back in the 90s and now it is going to be a lot fun to try this out!

[@vswitchzero]

Thanks for watching! Very nice, enjoy the new retro system 🙂👍

[@josephalbrecht3735]

@@vswitchzero I got the UMC 486 CPU today and it works just fine in the PC Chips M912 v1.7 motherboard. This motherboard has specific jumper settings for the UMC 486 CPU. Interestly, those jumper settings differ from a standard Intel 486SX.

[@aemerox5773]

You just answered a question that I was looking for for almost a decade. I remember talking about it a long time ago to KZbinr who went by the name WayBackTech and had made a review on UMC Green. I asked if this CPU was forbidden to be sold in the US, this doesn't include the rest of North America. This meant Canada and possibly Mexico could get their hands on one. Well that question was finally answered.

[@Fortunes.Fool.]

We had a Dell 386/25 and a friend’s dad had a Gateway 486/66. I was blown away how fast that was when we installed games on it. Seeing a Cyrix chip brought back 90s memories, so cool.

[@ahu747]

Bro i grrw up tinkering with 486dx 50s, dx2 66s, then a pentium 133. All your videos bring back so much memories

[@tech5882]

I built my BBS machine with UMC chip. It worked just fine while... it was cool. There was no a cooler designed specifically for the chip as far as I know. So I had to make my own cooling set up. Most of summer time case was wide open and had an additional desktop cooler blowing air into the case. :D

[@ninja011]

I used to have a system with a U5D in it. It was a custom tower built by a system integrator in Montreal when I lived there. I used it for school work and later upgraded it to a Pentium OverDrive socket-compatible CPU.

[@TalesofWeirdStuff]

I always thought it would be fun to pair a UMC Green with a Weitek 4167. Rare CPU + ultra rare FPU = 😍

[@vswitchzero]

Haha would be very cool 😁 .. hoping one day I’ll find a Weitek 4167.

[@Vanessaira-Retro]

Superb video! Great overview on this CPU.

[@vswitchzero]

Thanks so much! Glad you enjoyed it 👍

[@bigwave_dave8468]

Early on when the 486 came out, there was no low-power model. For that reason, we used a Cyrix 386 with an outboard fpu for a portable compute solution.

[@boardernut]

there were never a Cyrix 386 on the market.

[@davidfernengel1825]

Excellent video, thank you! What an interesting CPU. It's a pity they could'nt continue selling CPUs.

[@vswitchzero]

Thanks for watching! 🙂👍

[@tiemanowo]

Watching your videos, I can imagine what channels like JayTwoCents or GamersNexus would look like if they were posted videos from the 90s.

[@vswitchzero]

Haha that comment really makes my day 😁 .. thanks so much 👍

[@JeremyLevi]

Nice to see some performance tests for this rare bird and especially overclock performance. Now I'm curious how well it'd test out on a good VLB motherboard on those higher bus frequencies. I'd also be curious to see if there's any difference on your board with the jumpers set to standard Intel settings vs the UMC config just to see if there's maybe any chipset specific optimizations going on there to help out the UMC CPU performance.

[@vswitchzero]

Thanks for watching! I’ve never had much luck getting VLB to run stable at 50MHz, unfortunately. In my limited testing, I saw no difference between the UMC jumper settings and the Intel SX when it comes to performance. I wonder if it has something to do with the power features perhaps? Would like to look more into this at some point.

[@JeremyLevi]

@@vswitchzero That's a great point. It's certainly possible the UMC settings on the motherboard jumpers are related to the unique power saving features of the CPU.

[@rfmerrill]

It's so weird to be reminded that UMC has such a big presence and such "serious" products when they're also known as the biggest manufacturer of clone NES chips. Their NES CPU and PPU design are probably the most common ones to find besides Nintendo's own.

[@YarisTex]

All of us should spam UMC like crazy for them to do a production run of these 486’s on a more advanced node. 1GHz UMC 486

[@yournamehere23435]

I'd be interesting to see how fast a 486 could be just for the fun of it

[@virtualtools_3021]

​@@yournamehere23435especially wince just 6 days ago someone finally modded xp to work on 486

[@briangoldberg4439]

lol. what would you run on it?

[@jbaroli]

What bus frequency it would run? On which motherboard?

[@RuSrsbro]

​​@@jbaroliThey would have to engineer a way for the chip to run asynchronous to the bus speed, anything above 100 MHz is just not feasible

[@MarcoGPUtuber]

I picked up a few at the scrapyard. I think they're neat!

[@djlim4612]

I miss Cyrix. Used their 6X86 up to MII. Thanks to them, my family could afford to buy PCs for me and my siblings. Thanks for the video..I really haven't heard of UMC processors. Winchips, Cyrix , Nexgens ..wish they are still around.

[@JeremyLevi]

Same. I had both a Cyrix 5x86-100GP and later a M2 6x86MX-PR200 (150Mhz). The 586 was a bit of a stinker but the price was right and was still a big upgrade from my previous AMD 486DX40. The M2 was a great chip, ran flawlessly at a 75MHz bus x2 clock multiplier for years.

[@paulmcgrath2175]

I also had 150Mhz 6x86, mine had ibm markings, as they made the chips for cyrix.

[@djlim4612]

@@JeremyLevi Awesome. Mine was a 6x86 P-166+. And then the M2-333 came along. (My brother bought a Via Cyrix III thereafter but sadly i've never gotten to use it). All 3 were relatively slow in gaming but it was affordable and lower the bars of many families to owning a PC. Team Red all the way after the sad demise of Cyrix. Now my Cyrix 6x86 cpu is on display next to my Ryzen PC. Beautiful golden chip.

[@HappyBeezerStudios]

They sort of still are around. Cyrix sold the division to VIA which are still around and still make x86 chips. Cyrix MediaGX went to become AMD Geode NexGen were taken over by AMD and their RISC86 design powers the K5 WinChip were made by Centaur, then owned by IDT and later sold to VIA, where they made the C3and the succeeding designs, including the recent Zhaoxin stuff. And UMC are also still around and one of the biggest semiconductor producers worldwide.

[@djlim4612]

@@HappyBeezerStudios Agreed. But what i meant for them to be "around" is for them to still sell CPUs on the market to average joes, like AMD & Intel. Would be bloody awesome to have a battle between AMD Ryzen 7800x3d, Intel 14900K (if they don't explode beforehand) and "Cyrix CX 9000" yeah :D

[@3beltwesty]

We leased a pre pubic release beta 486 computer at a consulting firm. Its lease was about 1100 per month over say a year plus. It could do 3 different "passes" of Magnetic Recording Head modeling in say 12 hours; while our 386 took a day for One pass. OK by pass I mean just one set of parameters modeling the recording gap of a head for a 2.5 inch disc drive or a 3.5 drive. ei and turn the crank. 2 passes meant one varied ONE of the input variables. The darn cpu on the 486 ran hot as blazes since always doing the math modeling. So we ended up making a bigger heat sink and several fans so the thing would not lock up. The lease price of a grand a month was just for the 486 computer; not the software. That was say 1989 prices so righteous bucks

[@tapy5696]

It really was an amazing processor, when I first had the chance to test it I immediately ditched my Intel DX33. Its potential for overclocking resulted in the frequent addition of the designation by rogue vendors. I have a U5S-SUPER25-33 in my collection which was supposed to suggest its default operation at 33MHz.

[@KlopsKopp]

Love ur Gameboy Cartige Cases 😄

[@frankl1955]

"Don't Copy That Floppy"... In the early 90s I got a program written by some NASA engineers to bypass Copy Protection on floppies. They called it "Copy Fight protection" and that all info should be free to everyone. It was like the wild west of PCs.

[@retroboby007]

I have a motherboard with UMC chipsets, but I didnt knew they made CPUs. Very interesting stuff. And you have a cool testing system too. I saw your 486 dx2 66mhz reaching 49 score in 3d Bench. Very nice! My 486 dx2 66mhz never gets pasted 45 score in 3d Bench, even with VLB or PCI video card.

[@HappyBeezerStudios]

Time to tweak stuff. And check things like fastvid and mtrrlfbe

[@aleksandarsusnjar9574]

DX50 is for specialized systems and cases. Pair it with proper memory for memory-intensive processing or, with 50MHz-capable VLB video cards for it to shine.

[@envoycdx]

Do you mean use cases? Examples would be appreciated as I have a DX50 sat on the bench :)

[@JeremyLevi]

The trick was always finding VLB cards that ran stable at 50MHz. Maybe by now we know all the good ones but getting a stable config back in the day was a real case of trial and error. I knew more than one local beige-box PC retailers in those days that refused to build DX50-based systems for that exact reason, it just wasn't worth the support headaches.

[@mattelder1971]

@@JeremyLevi The DX2-66 was just all around better for most people. Lots of software just refused to run correctly on the DX50, even if the system was otherwise stable. However, I do recall one friend coming across one odd game (I can't recall what it was) that absolutely refused to run on ANY clock doubled chip, but worked perfectly on the DX50. It must have had some kind of timer or something that compared the bus speed and the clock speed and wouldn't run if they didn't match.

[@HappyBeezerStudios]

@@mattelder1971 makes me wonder what other processors that game can be forced to run with.

[@Ale.K7]

Great chip, great video!

[@ToTheGAMES]

Keeping CPU's in Gameboy cases is a smart idea! I'm gonna do that too, thanks!

[@a120068020]

I love the 486 collection!

[@xrysf03]

I recall booting Linux on a miniature embedded x86 motherboard, where the CPU would identify itself as UMC. Must've been during the noughties. Not sure if this could be an early VIA/SiS, rather I'm inclined to believe that this was something of the DM&P pedigree, i.e. and early Vortex86, a direct predecessor to Vortex86SX. Could it be that the modern Vortex chips inherit some history from the UMC 486 ? Perhaps by now there have been too many generations for any heritage to even matter, at the level of CPU core design... And yes the modern Vortex CPU's do feel like a very fast yet very lean 486DX+ (with CMPXCHG added). I believe around Vortex86DX the CPU was claimed to be "fully static", i.e. you could stop the clock for an indefinite time interval, and restart it and all the code would keep ticking (no data would get lost) - and it could be deeply underclocked, if you had to run stupid software that would not tolerate a CPU that's just too fast. Like down to 1/8th or even 1/16th. (A feature of the platform, accessible programmatically via some chipset registers, also available in the BIOS Setup on the motherboards by ICOP.)

[@unclemusclez]

really cool stuff

[@poseidon3032]

My dad bought me an AT IBM compatible mid tower that contained an AMD 386DX. When i got frustrated with trying to play Doom, found a computer shop in downtown of our city and upgraded the motherboard along with an AMD 486 DX2-80. Before the end of that era, I had outfitted it with an AMD 486 DX4-120. When later in 1999, I opted for a prebuilt eMachine with a Celeron 466 mhz, I gave it to a friend, much to my own chagrine. It ended up having 8 megs of memory, a WD 1.2 GB hard drive, a SCSI Plextor (I didn't research enough before I bought it) CD drive, Trident SuperVGA video card, Orchid sound card, and it ran Windows 95. I kick myself every day for not hanging onto it. I played Doom, Wolfenstein, Duke Nukem, Hexen, Xwing, Panzer General, and Myst on it. The Windows 95 disk even had the Rob Roy previev which i watched with fascination. The beginnings of what would later become the MPEG, WMV, QuickTime, and AVI video standards that we know of today.

[@ig8___]

I bought this when Starcraft released, upgrading from 66mhz to 120mhz - getting past the pentium 75hz required for Starcraft. Also 1st processor upgrade for me

[@predabot__6778]

Wow... I never had any idea about how GOOD UMC actually was at CPU-design! :O With 1-2 generations more they would easily have been a legitimate threat to Intel - which is probably why they sued to remove them from the playing-field. We need UMC to COME BACK into the biz! :) Interestingly enough, I believe there is another small Taiwanese company which has licensed UMC's technology and is currently producing on a very small scale, some x86 CPU's for the embedded market.

[@jonathanellis6097]

Intel.... stifling innovation since forever, the CPU market would be in a better place by now probably if UMC had carried on as a serious competitor. Intel were clearly scared.

[@baladi921]

I remember rocking a 486DX 100 in the 90s

[@HTMLEXP]

That stability in an under-voltage scenario would have made the UMC.486s great for laptops of the time I would have thought.

[@NaoPb]

But will it run the Windows XP that's been modded for 486 cpu's?

[@vswitchzero]

Would be really interesting to try! 🙂

[@jbaroli]

I had no clue that there is a WinXP version modded for 486

[@andrasszabo7386]

Where can I find XP for 486?

[@makingtechsense126]

What a trip down memory lane. In the early 90's my parents decided to buy a computer for the entire family to use. It had an Intel 486/SX-16 in it. Needless to say, it wasn't great. At some point we upgraded to an IBM 486DX2-66. I have never heard of the UMC Green 486 so thank you for sharing! Seems like UMC had a very talented engineering team. Too bad Intel killed off their CPU business.

[@ryanyoder7573]

There is no 486 SX 16. The 25 was the lowest clock speed 486 SX.

[@ryanyoder7573]

Hah. I checked Wikipedia and I was wrong. I built hundreds of computers back then but literally never saw a SX 16 or 20.

[@makingtechsense126]

​@@ryanyoder7573- No worries. I had to double check my memory too. Obviously it was an outlier.

[@vswitchzero]

They are actually quite difficult to find these days! Would love to find an SX-16 one of these days. They were typically only used in OEM machines. I believe the 16s were exclusively found in some Dell models.

[@mtm84a]

I'm just here admiring the use of gameboy cart cases to hold these chips

[@PixelPipes]

Man I didn't realize my Cyrix DX2-66 was so much slower than a real DX2-66 in most things :( ..........Oh hi there ebay!

[@Mr_Meowingtons]

Would have been sweet if they had came out with a dx2 or a dx4

[@HappyBeezerStudios]

They worked on a DX2, but it never went past engineering samples.

[@ausnorman8050]

Great Vid. I was just wondering on the 60Mhz OC, was unstable due to voltage or temp? Would putting anything on the ceramic top help dissipate the heat and make it 'more' stable?

[@vswitchzero]

I didn’t show it in the video but I had a decent sized heatsink and fan on the chip for all the overclocking tests. Cooling did help because the chip was always more stable when cool and would go down hill after running for 10 minutes or so. Would love to get a super-40 which is probably better binned. Thanks for watching! 👍

[@yugbe]

I remember thinking I was so great in 1996 with a dx4-100 in a laptop. Ah the good days of the wild west.

[@envoycdx]

Nice video there. typical of Intel to stomp down on the competitors though :(

[@Turktien]

Great vid!

[@doq]

The vendor string is "UMC UMC UMC " because the vendor string is 12 characters long and that pads it out perfectly. VIA Technologies had their vendor strings as "VIA VIA VIA " for the same reason.

[@wpyoga]

And they wouldn't repeat their name 4 times because the number 4 is perceived to be bad luck by the Chinese.

[@brano2yt]

Wow thanks, have that cpu in a computer in basement. Sadly the varta bios battery cut some traces on MB and needs to get fixed. Very interresting facts, didnt have a clue what a gem. Seemed just like another unknown low budget CPU.

[@vswitchzero]

Thanks for watching! 🙂👍

[@mwk1]

UMC z perspektywy Pegasusa - Szanuję! 😎

[@gordonlawrence1448]

The Cyrix 586 running at 50MHz stomped on some pentium systems and was way cheaper. Fantastic for running DOOM.

[@RetroTinkerer]

That is one cool rare CPU thanks for sharing!

[@runderwo]

4:10 This workaround was only possible until the WTO came onto the scene.

[@TheThorns]

I love the use of Gameboy cases for CPU's , LOL 😂

[@kthmhg]

Four years ago i buy locally my first 486 machine, that was Optimus with UMC 40-SUPER processor and no L2 Cache, it running on 25MHz, with 8MB ram and was install Windows 95. I almost shure that this processor run on this 25MHz frequency since production, i try to use 33 or 40 MHz, but system does not boot :/ So you should be very happy that your unit can be overclocked, my 40-Super can only be underclocked

[@vswitchzero]

Very interesting! Unless there is something specific about that board that didn’t like more than 25MHz - very strange. Perhaps it was defective. Thanks for sharing.

[@NexGen-3D]

The AMD overdrive was awesome, best 486 cpu i ever had

[@lQuadXl]

*UMC always misreads for me as* _UAC_ *from the Doom games!* 😂

[@kkolakowski]

Impressive! If they could manage to make clock-doubled or quadroupled with >100Mhz parts they could easily compete in low-end market way into 1995 & 96, where AMD 586 for example have been. Unfortunate.

[@everTriumph]

I seem to remember a version of the 486 to fit the 386 pinout, so you could upgrade your 386 system to 486 by just swapping the cpu. May even have one in the bits box.

[@vswitchzero]

Indeed! There were a few but the most popular was probably the Cyrix DLC. Hoping to do a video on it some day 👍

[@jermz79]

I remember seeing an ad for a 60mhz CPU at Fry's Electronics on the back page of a newspaper and thought they probably mixed up CPU speed and hard drive capacity.

[@tribaltalker1608]

I had a crazy off-brand IBM 486slc2 66MHz CPU in the early 1990's and it was such good value for money. A little faster than a 486sx-33 and much cheaper. Odd architecture though, it used a 386sx-style 16-bit bus with high clock rates and extra cache to make up the data transfer speed loss. No FPU of course.

[@vswitchzero]

Cool! Yes, the IBM blue lightning chips were very interesting CPUs. I hope to a video on it soon actually 👍

[@revcrussell]

Still working on building my all-UMC machine: chipset, processor, SRAM, VGA, super I/O

[@knightsun2920]

i actually had one in for a Win 98 reinstall during the time when it was released.

[@milescarter7803]

Power savings in this era is hilarious. We had 60w incandescent light bulbs back then.

[@SUCRA]

Great video. Amazing results for the Green CPU. If they did 3x multiplier version of it they would compete with the first pentiums. Very interesting!

[@vswitchzero]

Thanks, Bruno! 🙂👍

[@rootbeer666]

I'd be curious about a for clock comparison with 5x86 from AMD.

[@vswitchzero]

Thanks for watching! The Am5x86 has 16KB of write-back L1, so performance would be a bit better than the 8KB Intel/AMDs clock-for-clock. Wouldn’t be enough to close the gap with the UMC green though. Unfortunately I can’t run a 5x86 or DX4 at a 1x multiplier for a fair comparison.

[@WalrusFPGA]

Impressive numbers and OC capability from this little known chip! Loved the overview here. Thanks for sharing

[@vswitchzero]

Thanks very much! 🙂👍

[@awilliams1701]

The sad thing is people STILL think of intel for stability and speed. And it's not true. In fact Intel has found that stock clocked 13th and 14th gen chips are crashing. So they've had to pull back on them a bit. Meanwhile AMD ryzen is rock solid and even windows feels smoother.

[@movax20h]

Fascinating video. I always assumed UMC was just a clone, but it is own (and better) architecture. Sad, it died, we could have 3 players in the market maybe. I think the division speed is least of the interesting parts, as int division is rather rare instruction in most of the codes. So there is many other improvements they did to get to get perf.

[@tonecv]

And Intel 486 DX4 100mhz and AMD 586 133mhz (rare 150mhz) ???

[@vswitchzero]

Those are indeed very fast 486s with 16KB write back L1, but if you were to compare them clock-for-clock to the UMC green, the green would still be faster 🙂

[@BalancedSpirit79]

What an interesting little chip. Imagine if it was quad clocked and had an FPU.

[@Vic7bd]

Что то есть в этих керамических камнях замечательного.

[@markcentral]

No love in the charts for any IBM SLC chips 😔

[@SockyNoob]

Very impressive chips. A shame Intel sued them from existence. They were clearly mad they were being destroyed by UMC. An efficient chip is always best and literally became AMD and Intel's focus by the mid 2000s and everybody focuses on it now.

[@foxdavion6865]

UMC x486 models ended up being rarely on the market in Canada, Australia and New Zealand, Europe and the UK; For every 100 or so Intel or AMD chips, you'd come across one of these, very rare and were just floating around the place. How they ended up in these markets is a mystery because the only places they were common were Southeast Asia and Korea.

[@JeremyLevi]

I mean I can't speak for the other countries but here in Canada we had plenty of little Chinese / Taiwanese local hole-in-the-wall PC builder shops. I don't think it's a huge leap to assume that's probably who imported them to use in their builds.

[@foxdavion6865]

@@JeremyLevi Ah, makes a lot of sense to me.

[@LurchNZ]

AMD Am486DX5-133, that was the cpu to have during the 486 era.

[@electricroo]

Nice, I have an AMD 486 DX4-120SV8B. For a number of years I've been looking out for an old 486 laptop 40mhz buss with a socketed CPU to stick it in.

[@spladam3845]

Wow, that part is impressive, I wish I had access to these back in the day, I wonder how much they could be had for.

[@IBM_Museum]

The Intel S-spec 'SX911' (486DX2-66) shown during the intro is great for a baseline of the last Intel DX2 with the standard 8Kb Write-Through L1 cache - You need to get the 'SX955' S-spec for a comparison of any speed boost for Write-Back L1 as compared to Write-Through. That test is made slightly more easily at the Intel 486DX4 level since there are more batches to 16Kb L1 in WB or WT. Another note that the POD63/POD83 can be really nutty with L2 cache (typically 128 or 256Kb if present) on the motherboard.

[@HappyBeezerStudios]

Yeah, it comes pretty close to the 35 fps for doom, and that was recomended on a DX2-66

[@vswitchzero]

Thanks for your comment! I’ve been keeping an eye out for an SX955 and the DX/50 SX954. Would love to try them out. I do have an &EW DX4 with 16KB WB L1. Interesting that you mention that the POD can have issues with L2 cache. I was always surprised that the cache latency benchmarks were pretty poor with the POD. Thanks for watching 🙂👍

[@constantinosschinas4503]

Very interesting, never heard of this platform. Cyrix was noticeably slower than Intel. A thing tonavoid back then, especially if any graphic work was involved. In those days, power was marginal so anything slower was very obvious.

[@Finnisher_DAD]

Interesting, even as an European I had never even heard of these, always thought it was Intel, AMD or Cyrix at the time. Too bad they never got to evolve, imagine how they could have pushed Intel and AMD forward too if they were able to optimize architecture that much back then already. Fine might have been there was still room for such improvements and they were just the first to make it back then. Did the UMC have an FPU too?

[@GarthBeagle]

Crazy, had no idea these were that good!

[@testingchannel5440]

Unrelated question: where can I purchase the plastic cases you used to store the processors?

[@vswitchzero]

These are actually aftermarket GameBoy cartridge cases. I bought some 10-packs on Amazon and they are perfect for most retro CPUs 👍

[@oliver1224]

I used to own the IBM Blue Lightning CPU which I really wish I still owned. It was equivalent to a DX 2 66.. I believe it ran slightly faster...

[@HappyBeezerStudios]

Would be interesting to see more niche CPUs. Stuff like the Transmeta chips and how usable C3 and C7 were compared to their direct competitors.

[@RuruFIN]

Love those rare SX2s :)

[@sandmanxo]

I never knew there was anything special about these chips. Too bad they didn't hang around long enough to see the end of the 486 era. One of these cores clocked over 100mhz would have been great. I ran an amd 5x86 at 150mhz for a couple of years until the P54 prices came down. It ran early pentium era games reasonably well, even Quake was almost acceptable full screen, but it shined on integer based code of course. I bet this cpu core would trounce it though at 100 or 120mhz.