The GA-870A-UD3 rev 2.1 supports the Phenom II X4 965 (CPU part number HDZ965FBK4DGI). This model has a Thermal Design Power (TDP) of 140 Watts. There are no CPU's with a higher TDP supported.
The Thermal Design Power (TDP) is the average maximum power a processor can dissipate while running commercially available software. TDP is primarily used as a guideline for manufacturers of thermal solutions (heatsinks/fans, etc) which tells them how much heat their solution should dissipate. TDP is not the maximum power the CPU may generate - there may be periods of time when the CPU dissipates more power than designed, in which case either the CPU temperature will rise closer to the maximum, or special CPU circuitry will activate and add idle cycles or reduce CPU frequency with the intent of reducing the amount of generated power.
TDP is usually 20% - 30% lower than the CPU maximum power dissipation.
I'm not sure what correlation the Power Meter and Phenom II x 555 BE have, as the TDP of the Phenom II x 555 BE (CPU part number HDZ555WFK2DGM) is only 80 watts.