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It was a very interesting time in computing history. The changes from the i80286 to the i80386 were extreme - the i386 gave us a fundamentally different instruc

It was a very interesting time in computing history. The changes from the i80286 to the i80386 were extreme - the i386 gave us a fundamentally different instruction set that common 32 bit systems still use in 2023. On the other hand, the changes in the i80486 were purely about speed: relatively large built-in caches, integrated FPU, significantly better pipelining and so on. It was the last time Motorola really competed with Intel. The m68040 was all about performance, too, and Motorola's chip was faster in integer, floating point, synthetic and real world uses, clock for clock. (The m68060 was somewhat competitive with the Pentium, but people weren't choosing between x86 and m68k by then.) The x86 world really owes some thanks to Motorola for the competition. However, the fact that Intel was selling '486s like hotcakes meant they spent the time and money to continue to improve the '486, so the clocks went way up. The m68040 never had any clock improvements over 40 MHz. An i80486 system can still run NetBSD decently in 2023, which is a testament to the generally good performance of the CPU :)

chungy 4y ago
Intel pushed the 486 up to 100 MHz via the iDX4 chip (which lost the i486 branding, but it's still what it is). Initially intended for embedded systems, it was sold directly also to consumers with the "OverDrive" brand attached. (Maybe it was unsold stock from the embedded attempt?) AMD would further push its own 486 chips to 150 MHz, and I recall the raw clockspeed allowed it to stay competitive against the lower-end Pentiums (60-75 MHz), but architectural changes in the Pentium (branch prediction and out of order execution) really let the Pentium fly away from the 486 at fewer necessary cycles.
- mschaef 4y ago
  > Initially intended for embedded systems, it was sold directly also to consumers with the "OverDrive" brand attached. They also spent some effort marketing the DX4 as a low end alternative to the Pentium. It was possible to buy/build DX4 machines. Trouble there is the same as any other low end offering of the time - it got steamrolled by better technology coming down in price as quickly as it did. The window of opportunity for anything low end was not that large.
- LargoLasskhyfv 4y ago
  Overclocking the AMD Am5x86 486 processor to 160MHz! https://www.youtube.com/watch?v=ii0k5ahK9Cs https://www.youtube.com/watch?v=ii0k5ahK9Cs
mschaef 4y ago
> The changes from the i80286 to the i80386 were extreme It was the 386 that really put the platform's strategy squarely in the realm of general purpose computing. The 8088 and 8086 were intended as short term backfills for the gap left by the dismal performance and high cost of i432. The 8018x chips were targeted at the embedded space and the 80286 was targeted at phone switches. It was really something of an accident that the 286 worked in the PC AT class machines as well as it did. The 80386 was Intel's realization that they were successful in general purpose desktop computing and needed a product targeted specifically at that space, and with backward compatibility in mind.

chungy 4y ago

Intel pushed the 486 up to 100 MHz via the iDX4 chip (which lost the i486 branding, but it's still what it is). Initially intended for embedded systems, it was sold directly also to consumers with the "OverDrive" brand attached. (Maybe it was unsold stock from the embedded attempt?) AMD would further push its own 486 chips to 150 MHz, and I recall the raw clockspeed allowed it to stay competitive against the lower-end Pentiums (60-75 MHz), but architectural changes in the Pentium (branch prediction and out of order execution) really let the Pentium fly away from the 486 at fewer necessary cycles.

mschaef 4y ago
> Initially intended for embedded systems, it was sold directly also to consumers with the "OverDrive" brand attached. They also spent some effort marketing the DX4 as a low end alternative to the Pentium. It was possible to buy/build DX4 machines. Trouble there is the same as any other low end offering of the time - it got steamrolled by better technology coming down in price as quickly as it did. The window of opportunity for anything low end was not that large.
LargoLasskhyfv 4y ago
Overclocking the AMD Am5x86 486 processor to 160MHz! https://www.youtube.com/watch?v=ii0k5ahK9Cs https://www.youtube.com/watch?v=ii0k5ahK9Cs

mschaef 4y ago

> The changes from the i80286 to the i80386 were extreme It was the 386 that really put the platform's strategy squarely in the realm of general purpose computing. The 8088 and 8086 were intended as short term backfills for the gap left by the dismal performance and high cost of i432. The 8018x chips were targeted at the embedded space and the 80286 was targeted at phone switches. It was really something of an accident that the 286 worked in the PC AT class machines as well as it did. The 80386 was Intel's realization that they were successful in general purpose desktop computing and needed a product targeted specifically at that space, and with backward compatibility in mind.