The DX4 is the fastest member of the Intel 486 family. 75 and 100MHz versions are available. At an iCOMP index rating of 435, the 100 MHz DX4 performs up to 50% faster than the 66 MHz Intel DX2. The DX4's clock multiplier allows the processor to run three times faster than the system clock. This performance is achieved in part by a 16K on-chip cache (double that of the other 486s). The DX4 has an integrated floating point unit.
Like the other 486s, the DX4 achieves performance through a RISC integer core that executes frequently used instructions in a single clock cycle (the Pentium's can execute multiple instructions in a single clock cycle).
"IntelDX4" is the entire name, the "486" has been dropped and I am assured that there is no space in the same.