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Comment by jakedata | Hacker News Reader

"IBM PS/1 486-DX2 66Mhz, "Mini-Tower", model 2168. It was the computer I always wanted as a teenager but could never afford"

Wow - by 1992 I was on my fourth homebuilt PC. The KCS computer shows in Marlborough MA were an amazing resource for tinkerers. Buy parts, build PC and use for a while, sell PC, buy more parts - repeat.

By the end of 1992 I was running a 486-DX3 100 with a ULSI 487 math coprocessor.

For a short period of time I arguably had the fastest PC - and maybe computer on campus. It outran several models of Pentium and didn't make math mistakes.

I justified the last build because I was simulating a gas/diesel thermal-electric co-generation plant in a 21 page Excel spreadsheet for my honors thesis. The recalculation times were killing me.

Degree was in environmental science. Career is all computers.

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"Wow"? Is it really necessary to give this guy a hard time for being unable to afford the kind of computers you had in 1992?

Anyway, there's no such thing as a "DX3". And the first 100MHz 486 (the DX4) came out in March of 1994, so I don't see how you were running one at the end of 1992.

My family's first computer - not counting a hand-me-down XT that was impossibly out-of-date when we got it in 1992 or so - was a 66MHz 486-DX2, purchased in early 1995.

I can't quite explain why, but as a matter of pride it's still upsetting - decades later - to see someone weirdly bragging about an impossible computer that supposedly outran mine despite a three year handicap.

Is that really what "wow" means here? I took it more as "wow, I've been around forever / I must be old now" or something similarly tame.

That definitely brought back memories. Around '92, being a poor college student I took out a loan from my credit union for about $2,000 to buy a 486 DX2-50. For you younger people, that's about $4,000+ in today's money for a pretty basic computer. I dual booted DOS and Linux on that bad boy.

A 486DX and a 487? I thought the 487 was only useful for the SX chips?

...looked it up, apparently the standard 487 was a full 486DX that disabled and replaced the original 486SX. Was this some sort of other unusually awesome coprocessor I hadn't heard of?

Doubled throughput of certain calculations in certain tasks if motherboard supported it

Possibly something software like maple could take advantage of

The 486sx had a 16 bit external bus interface so it could work with 386 chipsets. The DX processors had a full 32 bit bus and correspondingly better throughput. The 486 never included an integrated FPU, you had to add a separate co-processor for that. I could go on about clock multipliers and base frequencies but I'll spare you.

I think you're thinking of the 486SLC

The 486SX was fully 32-bit (unlike the SLC and 386SX) and the 486DX had the integrated FPU, and the 487 was a drop in 486DX which disabled the 486SX

Exactly. I got scammed on my first PC when they sold me a 486 for the price of a 386. It was too good to be true. I later learned that the 486 was an SLC. Per say, a 386 with some internal cache from Cyrix (https://en.wikipedia.org/wiki/Cyrix_Cx486SLC).

You're wrong. The 486SX had a 32-bit bus, just like the DX version. The difference between them is that the DX had an integrated FPU while the SX had it disabled and you had to add a separate 487 co-processor.

You are thinking of the 386. You perfectly describe the situation on the 386 not the 486.

The 386SX had a 16 bit external bus interface so it could work with 286 chipsets. The DX processors had a full 32 bit bus and correspondingly better throughput. The 386 never included an integrated FPU, you had to add a separate co-processor for that.

Ya, I slept on it and realized I skipped a generation in my mind. I guess the details of one of the PCs I built 35 years ago fade after a while.

The 486DX had an FPU. It was the 486SX that lacked it. The "FPU" upgrade for a 486SX was a entire special version of the 486DX that disabled the original 486SX entirely.

Doesn't make any sense, perhaps it's AI-generated nonsense. There was a DX4 100 but no such thing as a "DX3". The 486 included an FPU so there'd be no reason to have a "487" which was a complete replacement for the 486SX chips. There were Pentium Overdrives but those were CPU replacements on the 486DX.

"It outran several models of Pentium and didn't make math mistakes." Total bragging rights. Total. You owned them. Good job.

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