Overclocking the AMD Am5x86 486 processor to 160MHz!

[@sqlcactuss]

Sold lots of these back when new I don't recall any of them not being able to hit 160Mhz. Most went on PCI based boards though. I do remember that even at 160Mhz playback of 128kbit/sec CBR was a problem for all 486 variants. I'm guessing due to the math co-processor. Good times.

[@xsc1000]

I played 128kb/s mp3 on AMD 486/160 with Winplay software. It doesnt work good with Winamp.

[@ВячеславТолкалин]

Winamp version 1.0 under Windows 95 also works well on 5X86, allowing you to listen to the base 128 Kbps, but requires at least 32 MB of RAM to minimize swapping. Version 2.X can also be made to work, but, I remember, you need to twist the settings of the MP3 decoder and turns the computer into essentially a single-tasking

[@spavatch]

I have no experience with 486 in that regard but I remember my Amiga 4000/040 was able to play MP3s up to 112 Kbps. Going for 128 requires some more juice (swapping the crystal to bump the CPU speed from stock 25 MHz to 30-33.

[@rd946]

Yeah, been running mine at 160MHz for at least 20 years with the help of an old Swiftech heatsink.

[@OzzFan1000]

I generally don't overclock my systems, but the things I've seen people do with theirs is quite impressive. The highest OC on these chips I've seen so far has been the CPU Galaxy channel here on KZbin - he was able to reach 200MHz with a PCI board. Anyway, awesome video!

[@vswitchzero]

Thanks, Charlie! I appreciate it! Yeah, CPU Galaxy did some amazing overclocking with his Am5x86 during the 486 quake race. I'm keeping an eye out for a board similar to the one he used - there are only a few good PCI based boards out there that can be used for pushing these that far.

[@andheeid]

back in the day.. i overclock my 486 dx4 to 160mhz so i can play 16 bit 44khz stereo mp3 file on winamp without stuttering.... ^_^

[@sinephase]

the confusing thing is the "P75" that makes you think it's a 75Mhz chip but it's supposed to mean it's equivalent performance as a pentium 75Mhz chip

[@mlodzin90]

I also have this CPU and it overclocks to 160MHz easily. I've also been able to overclock it to 150MHz with 50MHz FSB.

[@Xitrial]

Overlcocking with jumpers, the nostalgia, I remember overclocking my Pentium 200 mmx to 233 (or something like that I don't really remember well)

[@andrasszabo7386]

My brother once won an overclocking competition with a 233 MHz 486. Too bad he is not with us anymore to tell us the details.

[@1NIGHTMAREGAMER]

Check resistors and caps that may be bad could cause instability

[@1NIGHTMAREGAMER]

Say the board expects 5k of resistance but resister has weakened and became 4k

[@magnum333]

@@1NIGHTMAREGAMER So when resistors go bad they lose resistance? Does it happen often? When you say the capacitors, you mean the electrolytic capacitors or also the SMD ones?

[@RaimarLunardi]

how times changed when today my HDD (not even my SSD) is faster than the cache of an old CPU...

[@djpirtu2]

FYI: Cirrus 5434 VLB is quite fast card (waaay faster than superslow 5428) and it takes 50MHz VLB clock with no problems :)

[@binxyde]

I've got a GA-486-AM/S with this CPU for 40€ recently. This 160Mhz stable-working-beast will get my retro-daily 😋

[@Ozfrank]

486 and Pentium compaires as 1:2 by performance in fpu demanding programms. P75 = 486DX4-150 and P-90 is about DX4-200 (see extreme overclocked 486 video on youtube)

[@chelsona2574]

i had one of these as a kid... i forgot to put the heatsink back on one day when i installed memory and burnt it out lol.

[@VinnieMelo]

Funny to see today's type of reporting for old hardware. I remember benchmarking my computers with no "online" comparision.

[@framebuffer.10]

Cool! Retro-overclock is my favorite kind of overclock, nowadays 😎

[@vswitchzero]

Me too. I love that there are major performance gains you can get from simple BIOS tweaks too. You just don't see that any more.

[@kasimirdenhertog3516]

Had this chip back in the day, I thought it was so cool I made a website for it at GeoCities (remember that?) Got to help several owners overclock it. Great times, thanks for this revisit 🙂

[@aaronlochard7360]

Great video! One correction, that WDC card is not Western Digital, it's Western Design Center.

[@DaveDoc1984]

I hope its ok to ask a couple of questions? I have a 1996 PCI 486 Motherboard (Lucky Star 486E) as well as the CPU you have got in this video. I can get it to 160MHZ (although sometimes the machine won't boot) and Write Back Cache is enabled (CHKCPU confirms this). What RAM are you using in terms of type and speed (FPM or EDO and NS rating?). Likewise for Cache Chips?

[@vswitchzero]

Of course! In my case, I'm using 60ns FPM memory and 15ns SRAM for cache (32Kx8). I have another PCI based 486 system that supports EDO memory and have had some success with 50ns EDO. In my experience, it doesn't really provide a measurable performance benefit over FPM though (at least on this particular UMC 486 platform). For a 40MHz bus speed, 15ns cache should be considered the minimum without having to introduce a bunch of wait states. You could probably get away with 70ns memory at 1WS and a 40MHz bus, but 60ns would be better. Hope this helps.

[@CasioGreg]

i learned very quickly the difference between the 586 and an actual Pentium chip when a game i bought new would not run because the chip did not have the identifier to say it was a pentium

[@jonchapman6821]

Good stuff! 👏🏻 Happy to have found this channel.

[@vswitchzero]

Thanks, Jon! 👍

[@UncleMikeRetro]

Awesome video, Mike! In my opinion, this chip was when AMD first lashed out at Intel with core clock vs architecture. The epic Team Red versus Team Blue struggle starts... now! (or then!)

[@vswitchzero]

Thanks, Mike! Haha true, quite a few frequency vs architecture/ipc battles fought over the years between AMD and Intel. The roles reversed again with the second batch of K5 chips too 🙂

[@andreewert6576]

"You need Socket 7 now." - "No, you don't." "You need a slot-based CPU now, sockets don't scale." - "No, Socket 7 is still fine. Well okay we'll also make a slot soon but it'll beat the other guys!" "You need RAMBUS, 3GHz CPUs and ear protection to have a gaming system." - "Here, take this base model CPU and run it almost a GHz faster than advertized, we don't care! Yeah it's still below 100W then." AMD, how would the PC world have looked without you?

[@UncleMikeRetro]

@@andreewert6576 I think you have a super valid point! We need competition!

[@DaT0nkee]

This is what i did in the 90's. It was almost as fast as an Intel Pentium 66. Exactly the same results here.

[@roadsiderebels3039]

Is your DOS Benchmark Pack available?

[@vswitchzero]

The DOS benchmark pack I used was created by PhilsComputerLab. You can find it at his site here: www.philscomputerlab.com/dos-benchmark-pack.html

[@BrassicGamer]

Looking forward to comparing the performance of your system to mine, which is PCI and uses EDO RAM. I immediately suspect that I am guilty of doing NO tweaking in the BIOS whatsoever, so hopefully I can make some gains! Glad it worked. Makes Duke 3D much more playable.

[@OCROldComputerRebuilds]

That was about as high as my chip would all me to go. nice to this in action. Great video Mike.

[@vswitchzero]

Thanks, Patrick! Was a lot of fun getting it going 👍

[@ianbrisland1982]

Brings back so many memories looking at that board, and the smell as you brought them out of the antistatic bag :) good times

[@magnum333]

On some motherboards 150MHz is actually faster than 160MHz because you run the bus at 50MHz (x3). Maybe not on that board but you should give it a try!

[@vswitchzero]

Yes indeed! I couldn’t run 50MHz stable on this board but if you check out my upgrade chip showdown video I include some results at 3x50 and 4x40 for comparison (on a different PCI based board)👍

[@magnum333]

@@vswitchzero Great! I'll check it out

[@DracoDan2]

Money was tight back in the 1995 but I convinced my parents to upgrade our 486sx 25 with a new computer. After trying my best to convince them to go with a Pentium based system, the low price of an AST computer with this CPU won out. It was definitely an upgrade to the sx 25 bought all my friends had Packard Bell Pentium systems that ran circles around it.

[@AncapDude]

I had such a CPU in a VLB system back in the 90s but ran it at stock 133 MHz that was good enough for almost everything except Quake :)

[@TechAmbr]

Very nice. That brings back some memories. My personal system back in the 90s (high school!) was a UMC VLB board with an Am5x86 very similar to this one. Hexen, Duke3D, Descent, Doom II... I loved that machine so much. This was a great trip down memory lane. I vividly remember that Quake framerate! 😆 I never overclocked mine -- I wonder if it could've also done 160MHz? Ah well, speculation at this point. Thanks for the video!

[@vswitchzero]

Thanks for your comment! Yeah they were really awesome CPUs, that's for sure! We had a DX2/66 VLB system around 1994. It was an excellent chip at the time, but many of the later DOS games I played got choppy at times. Eventually we got a second system, which was a Pentium 100. It felt like a really significant performance boost from what I recall.

[@TechAmbr]

@@vswitchzero Oh yeah! And if you made one of those upgrades -- coming from a pre-PCI 486 system to a 2nd-generation Pentium on Socket 5 or Socket 7 -- you got not only the CPU performance uplift, but the platform uplift as well! It wasn't uncommon for an upgrade like that to double your apparent-performance-per-clock! Pentium was a big deal back in the 90s! These are the kinds of huge strides in CPU performance that I feel like we don't see that often these days. It made this era of PC building really exciting

[@televiciousgoober]

Keeps the room toasty too.

[@simonkormendy849]

I remember watching a youtube video where a guy overclocked a P4 CPU (I think) to some insane speed, but they forgot to put the CPU cooler fan back on before they powered-up the system, it ran fine for something like 20 seconds or so, then there was a loud bang and then the guy in the video was shocked to find that the CPU had literally exploded and blown a huge hole right through the motherboard, pretty hilarious.

[@simonkormendy849]

From what I've read, the main downside to overclocking CPUs is that you put increased strain on it and there's an increased risk of wearing it out, that's aside from the potential instability issues.

[@GewelReal]

75MB/s on L1 cache... Cheap pendrives are faster than that today wow

[@trex70]

I needed that 30 years ago 😁

[@SockyNoob]

Really cool that it can slow down to a 386 when turbo is disabled. That really makes it worthwhile imo.

[@dallesamllhals9161]

So INTEL just said: "DX4 sounds better than DX3"?

[@vswitchzero]

Haha yeah, I always wondered why they didn't just call it DX3 since it had a 3X multiplier. According to the Intel DX4 wikipedia page, it was renamed due to some trademark issues with AMD. Don't really know the detail behind it though.

[@dallesamllhals9161]

@@vswitchzero But why do "we/some" now call the Am5x86-P75 a DX5? (sigh) Ah yes: Intel vs AMD (a bit of Cyrix) and their: ™®©They had fun in the 80s...90s...and all still do ;-P If 'murican - I should've been a Lawyer with Copyright expertise!

[@nayicirci523]

Great video!!

[@JamieBainbridge]

That's really decent Quake results for a 486!

[@nexxusty]

We should get together and do some Canadian LN2 retro OC fun.

[@O.Shawabkeh]

Good presentation. I wonder if the WDC card held you back. Maybe a Cirrus Logic or S3 would bring better frames in Doom2/Quake.

[@vswitchzero]

Thanks for your comment! I did some testing with a Cirrus Logic GD5428 and a Trident card on this system earlier actually. The WD card is actually quite a bit quicker than both of them. It has about a 5-6 FPS advantage over the Cirrus Logic card. That requires the undocumented 0WS jumper to be set on the WD card though 🙂 - I've been keeping an eye out for an ARK1000 VLB card, which should be one of the quickest.

[@O.Shawabkeh]

@@vswitchzero interesting. Never guessed WD could pull that much. Thanks for your reply!

[@федов-ф4х]

i had the same during my childhood in 90s. overclocking it to 160 mhz too. and the heatsink was without fan! its heating more than 100 C! but i was stupid child without internet so i think its ok. and it was ok! but! in GTA - if you make car crash - its stucks and reboot. btw - if you overclock it to 160 mhz its shown in bios p-raiting p90! but it was not - quake works very bad on it

[@vswitchzero]

I noticed that too. When I overclock it to 160MHz on my Shuttle motherboard, the BIOS reports an AM5x86-P90 also. I wonder if that was actually a planned product at some time :)

[@enzito_sdf6978]

i love these old 486s, i'm messing with and old opti 895 board i got and it works just great. same issue with the L1 writeback cache though, i managed to get it working by soldering some wires but it completely kills the turbo functionality (the pc just freezes), so whatever, it's not worth the hassle for a few fps anyways.

[@vswitchzero]

I had the same issue with a UMC based board. Write back L1 doesn’t seem to play nice with the turbo function on many boards.

[@garyglitta]

I think that it’s more likely that the capacitors in the crystal oscillator circuit are no longer working right / have drifted such that the oscillator is not stable. It’s crucial to match these in order to create the resonant effect and a stable oscillation.

[@garyglitta]

Not sure how my comment ended up here, it was of course meant for the GUS video

[@WhitfieldProductionsTV]

back in the day when amd was actually good.

[@nezhakan]

Is it comparable with pentium overdrive on default clocks?

[@vswitchzero]

It all depends on the benchmark. Each chip has their strengths and weaknesses. I will be doing a showdown soon between the AM5x86, Pentium overdrive and Cyrix 5x86 including some overclocking results :)

[@javi30nkp]

sorry , but this cpu can give 200 mhz another u tuber make up posible find it , it is very interesting channel like u :)

[@kasimirdenhertog3516]

CPU Galaxy is the channel you’re referring to

[@javi30nkp]

@@kasimirdenhertog3516 abandoned Channel what a pity :(

[@kasimirdenhertog3516]

@@javi30nkp no! It seemed that way, but he returned, just last week or so! Check it out, he's posted a nice video about replacing a 486SX-16 with a Kingston 133MHz.

[@kasimirdenhertog3516]

Here: kzbin.info/www/bejne/fGnck6Z5d9Cal8k&si=EnSIkaIECMiOmarE

[@Phil-D83]

I had one lf those 5x86 overdrive chips. Still sucked for gaming vs the 486 dx2 66

[@dallesamllhals9161]

Really? Doesn't make sense. A DX2 at 66MHz vs A (real)DX4 at 133MHz.

[@toxy3580]

Plug it in to 240v and try get it to 10ghz or else you are not a real overclocker