A 4.3-GHz voltage controlled oscillator (VCO) using an addressable array of cross-coupled minimum size NMOS transistor pairs for post fabrication selection is demonstrated in 65-nm CMOS. An algorithm based on Hamming distance using the phase noise measurements of ~1,500 array combinations was used to identify combinations that have record phase noise of -130dBc/Hz at 1-MHz offset from a 4.3-GHz carrier, while consuming 5.2 mW from a 1-V supply. The operating frequency of circuits using post fabrication selection in its high frequency path is increased to 5 GHz.