ALL NEWS DELLS OptiPlex™ desktops and Precision™ workstations REQUIRE PURE SINE WAVE UPS's?

DELL™ OPTIPLEX™ 390 TECHNICAL GUIDEBOOK —FINAL
POWER
NOTE: These form factors utilize a more efficient Active Power Factor Correction (APFC) power supply. Dell recommends only Universal Power
Supplies (UPS) based on Sine Wave output for APFC PSUs, not an approximation of a Sine Wave, Square Wave, or quasi-Square Wave. If you
have questions, please contact the manufacture to confirm the output type.
Power Protection & Back-up

 In the case of a power outage, be prepared with an Uninterruptible Power Supply (UPS) that can provide business continuity to prevent critical data loss. For Dell OptiPlex™ desktops and Precision™ workstations that utilize Active Power Factor Correction (APFC) power supply units, Dell recommends Universal Power Supplies (UPS) based on Sine Wave output, not an approximation of a Sine Wave, Square wave, or quasi-square wave (see UPS technical specifications).
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