Digital predistortion (DPD) performance for an IEEE 802.11ac WLAN transmitter in 28 nm CMOS, using 20 and 80 MHz bandwidth with 256QAM modulation, is analyzed under different bandwidth limitations. Due to band-limited conditions in the transmitter chain, the DPD linearization performance may be reduced. For a minimum transmitter error vector magnitude (EVM) requirement of -32 dB (2.5%) for 256QAM modulation, a reduction in the maximum linear output power of 1.6 dB due to bandwidth limitations in the transmitter chain is estimated using simulations and measurement results.