I can't seem to find a clear answer whether my AT&T Atrix will work on VZW. I see the atrix works on the following frequencies: GSM 850 / 900 / 1800 / 1900 HSDPA 850 / 1900 / 2100 Mhz Verizon operates on the 850 mhz and the 1900 mhz frequencies on the CDMA spectrum. I'm reading that HSDPA is "an evolution and improvement on W-CDMA" (What is HSDPA?). Does this mean the phone will work with VZW as long as it's unlocked and I pop in a SIM card? Sorry if this is a dumb question. I realize verizon is supposedly coming out with its own Atrix, but I already own the AT&T model and I'm just trying to figure out my options for service providers.