Dell OptiPlex 790 (Early 2011) - Manual (Page 11)

Power
Small Form Factor 240 W
Ultra Small Form Factor 200 W
Maximum heat dissipation
Mini-Tower 1390 BTU/hr
Desktop 1312 BTU/hr
Small Form Factor 1259 BTU/hr
Ultra Small Form Factor 758 BTU/hr
NOTE: Heat dissipation is calculated by using the power supply wattage rating.
NOTE: See the safety information that shipped with your computer for important
voltage-setting information.
Physical
Height
Mini-Tower 36.00 cm (14.17 inches)
Desktop 36.00 cm (14.17 inches)
Small Form Factor 29.00 cm (11.42 inches)
Ultra Small Form Factor 23.70 cm (9.33 inches)
Width
Mini-Tower 17.50 cm (6.89 inches)
Desktop 10.20 cm (4.01 inches)
Small Form Factor 9.26 cm (3.65 inches)
Ultra Small Form Factor 6.50 cm (2.56 inches)
Depth
Mini-Tower 41.70 cm (16.42 inches)
Desktop 41.00 cm (16.14 inches)
Small Form Factor 31.20 cm (12.28 inches)
Ultra Small Form Factor 24.00 cm (9.45 inches)
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