Finally after eight years of hard working on the CPU with the codename F86, Nexgen announced to the world the Nx586 in March 1994. Although it was fully compatible with the i386 instruction set, the design was far more advanced. The Nx586 could process two instructions in one clock cycle (superscalar) and had 32KB L1 cache (16KB instruction & 16KB data). But many more new technologies were incorporated in the design like advanced branch prediction and 64bit busses. Something else Nexgen pioneered was the inclusion of the L2 cache controller in the CPU, this allowed for much faster L2 cache access. Last but not least; the Nx586's most famous feature; the RISC86 microarchitecture.

The Nx586 had a fixed FSB - Clock ratio, the FSB was always half that of the CPU clock. The P90 version for instance had a FSB speed of 42MHz and a clockspeed of 84MHz. Compared to the Intel Pentium 84MHz is an odd speed, but Nexgen used the infamous P-rating. The P-rating showed how the CPU performed in comparison to an Intel Pentium.The NexGen Nx586 P90 would perform equal or better than an Intel Pentium 90MHz.

In reality the integer performance was more or less the same as a Pentium. But as the Nx586 lacked a co-processor, the floating point performance was far behind. The Nx586 was a good DOS CPU, but in Windows 3.1 the performance was less, compared to the Pentium.

As long as the Nx586 had no co-processor it would remain slower than Intel´s Pentium. It took NexGen until November 1995 to finish the design of the Nx587 co-processor and integrate it with the Nx586 on one chip.

The Nx586 processor itself did not support the CPUID feature, the BIOS of the motherboard could load that microcode. Unfortunately this did not work with the older BIOS's. The only way to be sure what speedgrade the CPU had was the print on the processor itself or looking for the jumpers J3 (NxVL) or J9-J10-J11 (NxPCI) on the motherboard. However, some software wanted to know what CPU it had to work with. Windows95 for instance would not install on a Nexgen system. To 'fool' Windows, Nexgen released a small program (IDON.COM) which tells the windows CPU detection routine that the Nx586 is a 586 class CPU. Later models, the P120 and P133, would incorporate the CPUID feature.