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From a software point of view, the instruction set of the 486 family is very similar to its immediate predecessor, the Intel 80386, with the addition of only a few extra instructions.

From a hardware point of view, however, the architecture of the 486 is a vast improvement. It has an on-chip unified instruction and data cache, an optional on-chip floating-point unit (FPU), and an enhanced bus interface unit. In addition, under optimal conditions, the processor core can sustain an execution rate of one instruction per clock cycle. These improvements yield a rough doubling in performance over an Intel 80386 at the same clock rate. However, some low-end 486 models were actually slower than the highest-speed 386s, especially so with the 'SX' 486s.

A 25 MHz version was introduced in April 1989, a 33 MHz version in May 1990, and a 50 MHz version in June 1991.

There are several suffixes and variants including:

• Intel 80486SX - a 486DX with its FPU disabled, although the earlier variants were simply normal 486s with defective FPUs. In later versions, the FPU was removed from the die to reduce its area and thus reduce cost.
• Intel 80486DX - same as above, with a working FPU.
• Intel 80486DX2 - the internal processor clock runs at twice the clock rate of the external bus clock.
• Intel 80486SX2 - same as the 8046DX2, but with the FPU disabled.
• Intel 80486SLThe Intel 80486SL is the power-saving variant of the Intel 80486DX microprocessor. The SL was designed for use in mobile computers. It was produced between November 1992 and June 1993. Clock speeds available were 20, 25 and 33 MHz. The 486SL contains all - 486DX with power conservation circuitry. Mainly for use in portables computers.
• Intel 80486SL-NM - 486SX with power conservation circuitry; SL enhanced suffix, denotes a 486 with special power conservation circuitry similar to that in the 486SL processors.
• Intel 80487The Intel 80487 or 487 (i487), was the " math coprocessor " for the Intel 486SX chips. It was essentially a full blown 486DX chip with a pin that knocked out the 486SX into a sleep mode, while it took over full processor duties. Intel 487. - 486DX with a slightly different pinout for use in 486SX systems as a FPU.
• Intel 80486 OverDriveIntel 80486 OverDrive processors were a category of various Intel 80486s that were produced with the designated purpose of being used to upgrade personal computers. An Intel DX4-100MHz OverDrive with built-in heatsink & voltage regulator. OverDrives typic - 486SX, 486SX2, 486DX2 or 486DX4. Marked as upgrade processors, some models had different pinouts or voltage handling abilities from 'standard' chips of the same speed stepping.
• Intel 80486DX4The Intel DX4 is a clock-tripled 80486 microprocessor chip. Intel named their chip deceptively during litigation with AMD over trademarks. The product was officially named the DX4, but OEMs continued using the 486DX4 naming convention. Intel produced DX4s - designed to run at triple clock rate (not quadruple as often believed).

External clock rates include 16 MHzA megahertz (MHz is one million (106) hertz, a measure of frequency. Megahertz in radio When used in the context of radio, MHz refers to the number of oscillations of electromagnetic radiation. Severel parts of the radio spectrum fall into the MHz range:, 20MHz, 25MHz, 33MHz, 40MHz and 50MHz. Some later 486 motherboardA motherboard also known as mainboard logic board or systemboard is the central or primary circuit board making up a complex electronic system, such as a computer. A typical computer is built with the microprocessor, main memory, and other basic components provided unofficial and undocumented support for 60 and 66MHz, however.

The 486 processor has been licensed or reverse engineeredReverse engineering (RE) is the process of taking something (a device, an electrical component, a software program, etc. apart and analyzing its workings in detail, usually with the intention to construct a new device or program that does the same thing w by other companies such as IBM, Texas Instruments, AMD, Cyrix, and Chips and Technologies. Some are almost exact duplicates in specifications and performance, some are not.

The successor to the 486 is the Pentium processor.