Intel DX4

[1] Intel named it DX4 (rather than DX3) as a consequence of litigation with Advanced Micro Devices over trademarks.

A version of IntelDX4 featuring write-back cache was released in October 1994.

The original write-through versions of the chip are marked with a laser-embossed “&E,” while the write-back-enabled versions are marked “&EW.” i486 OverDrive editions of IntelDX4 had locked multipliers, and therefore can only run at 3× the external clock speed.

IntelDX4 was an OEM-only product, but the DX4 Overdrive could be purchased at a retail store.

Motherboards lacking support for the 3.3-V CPUs can sometimes make use of them using a voltage regulator module (VRM) that fits between the socket and the CPU.

Intel DX4 100 MHz
Voltage converter for DX4 processors (5 V to 3.3 V)
An IntelDX4 FC80486DX4-75 SX883 75 MHz (3× 25 MHz) 16 KB cache L1 WT. This unit was made in January 1995, and was taken from a Toshiba laptop.
Intel DX4 Overdrive